title: Offside rule

text: The offside rule is one of the oldest football rules, but is still a much discussed rule. This is probably because of the relatively complicated set of provisions provided by the sport's law-making body, the IFAB for deciding if a player in an offside position is actually guilty of an offside offence by becoming involved in active play. It can also be a difficult decision for the referee or assistant referee to make as they need to watch the ball, the player playing the ball and also the attacker who is seeking to receive the ball at the same time.


title: Offside rule

text: Offside is an offence committed by the team which has the ball and is punished with an indirect free kick.


title: Offside rule

text: It is a common misconception that the ball must be played forward for an offside offence to be committed. This is incorrect however, as an offside offence is related to the position of the player in relation to the last two opponents, the ball and the opponent's goal line rather than the direction the ball is played. If the player is closer to the opponent's goal line than both the ball and the second-last opponent when it is played by a team mate, she or he is in an offside position.


title: Kuwait

text: Kuwait is the most socially progressive country in the Gulf region. It has a small and rich economy. It has about 96 billion barrels of crude oil reserves. Crude oil reserves are the oil that is still under the ground and has not yet been cleaned up. Kuwait has 10% of all of the oil reserves in the world. The country makes a lot of money by selling oil. This money is almost half of all the money the country makes. The oil money is also 95% of the money made by selling things to different countries (people call that exports). Also, the oil money is 80% of the money the government makes. Kuwait is now talking with oil companies of other countries to make oil fields in the northern part of the country.


title: Kuwait

text: Kuwait's weather makes farming hard (too little rain). Instead of farming, the country catches fish and buys food from other countries. About 75% of the country's water to drink has to be distilled (have the salt removed) or purchased from other countries.


title: Kuwait

text: In 1990, Iraq invaded (brought an army in to fight against) Kuwait. This started the first Gulf War. Kuwait's official religion is Islam, although 15% of its population are Christian or Hindu. Arabic is mostly spoken in Kuwait but English is widespread among Kuwaitis (residents of Kuwait). Kuwait is one of the few nations that has education for every age.


title: Kuwait

text: CDR (per 1000) for 2004 1.9. Growth Rate(%) for 1992-2002 2.1. the Total Fertility Rate for 2002 is 2.7. Percent population is living in urban in 2003 96.2.Per capita gross national income ($) 2002 612. Population Density( per square kilometer) in 2000 107.4


title: Kuwait

text: Infant Mortality Rate (per 1000)for 2005 9.95. Adult literacy rate (85%) female literacy rate (81%) (2002).


title: Kuwait

text: Kuwait is divided into 6 governorates. The governorates are divided into districts, And the establishment of the governorates of Kuwait dates back to the Emiri Decree No. 6 issued in 1962, which divided Kuwait into three governorates: the Capital Governorate, Hawalli Governorate and Al-Ahmadi Governorate. The decree clarified the work of the governor, his subordination of the governor to the Ministry of Interior, and his responsibility towards security, provided that the Ministry of Interior issues the necessary decisions to indicate the limits of the governor's jurisdiction. There have been some changes regarding the governorates of Kuwait, which we summarize as follows:


title: Kuwait

text: . On November 14, 1979: Some provisions of the administrative division decree were amended so that a fourth governorate, Al-Jahra Governorate, was added.


title: Kuwait

text: . On October 12, 1988: The first article of the article was amended to divide Kuwait into five governorates by adding Al-Farwaniyah Governorate.


title: Kuwait

text: . On November 27, 1999: Emiri Decree No. 290 was issued to add a sixth governorate, Mubarak Al-Kabeer Governorate.


title: Kuwait

text: Thus, Kuwait has become administratively divided into six governorates, each affiliated with several regions. Warba Island and Bubiyan Island belong to the Jahra Governorate, while the rest of the islands belong to the Capital Governorate.


title: Market

text: A market is a place where people go to buy or sell things. When people have products to sell, they set up a market place. There may be a special building for the market place, or the market may be held in an open space where the sellers can put up a stall (like a kind of tent) and then take the stall down at the end of the day.


title: Market

text: The word market can also have a more general meaning in the economy. It can mean the way things are bought or sold. "There is a big market for dishwashers" means that lots of people want to buy dishwashers, so therefore a business that makes dishwashers is likely to be able to make a lot of money. When things are sold, people buy the product, and this "stimulates the economy" (helps people to spend and earn money). The market needs to balance supply and demand. There is no point in supplying (making) lots of dishwashers if people do not want them. In the market prices may change quickly if supply or demand changes.


title: Market

text: If a seller of a good cannot supply what customers want or ask for too high of a price, other sellers may try to supply that good. If other sellers enter the market for that good, in competition, that will tend to fulfill demand and lower prices. Sellers who do not like competition may try to kill the competition. This would establish a monopoly, and many countries have laws to protect the free market against such practices.


title: Latin script

text: Latin or Roman script, is a writing system used to write many modern-day languages. It is the most used writing system in the world today. It is the official script for nearly all the languages of Western Europe and of some Eastern European languages. It is also used by some non-European languages such as Turkish, Vietnamese, Malay language, Somali, Swahili and Tagalog. It is an alternative writing system for languages such as Serbian and Bosnian.


title: Latin script

text: The alphabet is a writing system which evolved from a western variety of the Greek alphabet. It was the Etruscans who first developed it after borrowing the Greek alphabet, and the Romans developed it further. The sounds of some letters changed, some letters were lost and gained and several writing styles ('hands') developed. Two such styles were combined into one script with upper and lower case letters ('capitals' and 'small letters'). Modern capital letters differ only slightly from their Roman counterparts. There are few regional variations.


title: Latin script

text: The modern version of the alphabet is used for writing many languages. Indo-European languages, especially those of Western Europe, are mostly written with the Latin alphabet. These languages include the Germanic languages (which includes English, German, Swedish, and others) and the Romance languages (which includes French, Spanish, Italian, Portuguese and others). There are of course Indo-European languages that do not use the Latin alphabet, like Greek and Russian, as well as non-Indo-European languages that do, like Vietnamese.


title: Latin script

text: Nearly all languages using the Roman alphabet include diacritics, which are symbols found above or below the letters. They are used for things such as tones and pronunciation. English is the only major European language that does not have any of these marks, at least not for native words. Words taken from other languages sometimes use diacritics to make clear the correct pronunciation.


title: Latin script

text: The Roman script has fewer letters than the sounds in some of the languages that use it. Some languages make up for the lack of letters by using diacritic marks, such as ă, â, á, à, ä, é, ë, í, î, ó, ö, ô, ẹ, ị, ọ, ụ, ã, ả, ẻ, ỉ, ỏ, ủ, ñ, ç, č, ď, ě, ľ, ł, ň, ř, ŕ, š, ș, ť, ț, ú, ů, ü, ý, ž, đ and other similar. In effect, this increases the number of letters in their alphabet. Languages which use "some" of these characters are French, Czech, Polish, Hungarian, Romanian, Spanish, Turkish, Tagalog, Vietnamese, Esperanto, Igbo and many other.


title: Latin script

text: Many languages changed their writing systems to the Latin script. In some countries, Europeans made native people use it. The Vietnamese language was written in Chinese characters, and there is a Chinese-based Vietnamese writing system called chu nom. However, Chinese script requires a large number of characters to be learnt before a person is truly literate. The Vietnamese government switched to the Latin alphabet in the early 20th century so they could increase the country's literacy rates. The Vietnamese kept using the Latin alphabet even after independence since it was much faster to learn than Chinese characters (chu nom).


title: Latin script

text: After the Russian Revolution, when the Russian Empire fell, the Latin alphabet in Turkic countries was started by Azerbaijan in 1918. When the Soviet Union broke up, some of its smaller languages began using the Latin alphabet. It is now used in Turkmenistan, Uzbekistan, and Azerbaijan. Kazakhstan announced in 2018 that the Latin alphabet would become the Kazakh language's main writing system.


title: Latin script

text: Changing the way a language is written to Latin letters is called romanization. Many people who do not speak the language read a romanized version to know roughly how the words will sound, even if that is not the normal way to write the language. Some languages, like Chinese and Japanese, use the Latin alphabet in their languages so that they can be typed on a computer more easily. In mainland China, pinyin is the official romanization for Mandarin Chinese, and it is used to type Chinese characters on the computer by typing them phonetically. Even though many Japanese computers have kana keyboards to type Japanese on the computer, Japanese can also be typed using the Latin alphabet. Software called IME (input method editor) converts the Latin letters, called romaji in Japanese, into Japanese kana and kanji.


title: Agorism

text: Agorism is a free-market anarchist political philosophy founded by Samuel Edward Konkin III that believes the ultimate goal as bringing about a society in which all "relations between people are voluntary exchanges– a free market." The term comes from the Greek word "agora," referring to an open place for assembly and market in ancient Greek city-states. Agorist theory divides people into two classes: people who make their living through the market, and people who make their living by coercing others (called the "economic class" and "political class", respectively). They support a nonviolent overthrow of the second class by the first, through peaceful black market and grey market activity, known as counter-economics.


title: Hippopotamus

text: The hippopotamus ("Hippopotamus amphibius"), or hippo, ancient Greek for "river horse" ("Ιπποπόταμος"), is a large mammal in Africa that usually eats plants. It is one of only two species in the family Hippopotamidae that are still alive. The other is the pygmy hippopotamus.


title: Hippopotamus

text: The hippopotamus is the second largest land animal in size and the third largest land animal in weight. The elephant is the heaviest and the white rhinoceros is the second heaviest, but a bit smaller than the hippo. The hippo is also the heaviest artiodactyl.


title: Hippopotamus

text: The hippopotamus is semi-aquatic. This means that even though it usually lives on the land, it spends a great amount of time in rivers and lakes where males lead groups of 5 to 30 females and young. In the daytime, they keep cool by staying in the water or mud. They give birth to baby hippos in the water, too. At dusk, they come out to graze on grass. Hippopotamuses rest together in the water, but they like to graze by themselves.


title: Hippopotamus

text: The hippopotamus has: a torso that is shaped like a barrel, a very big mouth and teeth, an almost hairless body, short legs and great size. It is the third largest land mammal, judging by its weight, which is between between 1½ and 3 tonnes. The white rhinoceros weighs 1½ to 3½ tonnes and the three species of elephant weigh 3 to 9 tonnes. Even though it has short, fat legs, it can run more quickly than a human. Some hippos have run at 30 km/h (19 mph) for short distances. The hippopotamus is one of the fiercest animals in the world. It is often called one of the most dangerous animals in Africa. There are about 125,000 to 150,000 hippos in Sub-Saharan Africa. Zambia (about 40,000) and Tanzania (20,000–30,000) have the most hippos. They are threatened because they are losing their habitats and being poached for their meat and ivory teeth.


title: Hippopotamus

text: The word "hippopotamus" comes from the ancient Greek , "hippopotamos", from , "hippos", "horse" and , "potamos", which means "river". So, "hippopotamus" means "horse of the river". More than one hippopotamus are called "hippopotami", and 'hippopotamuses' or 'hippos' is also used. Hippopotami are social. About 30 hippos live together in groups. A male hippopotamus is known as a bull. A female hippopotamus is called a cow and a baby hippo is called a calf. The species is also known as the common hippopotamus or the Nile hippopotamus.


title: Hippopotamus

text: Hippopotami are the fourth largest mammals in the world (after whales, elephants and rhinoceroses). The Egyptian hippopotamus is smaller than the others. They can live in the water or on land. They can walk or even run along the bottom of a river.


title: Hippopotamus

text: Because hippos are so large, it is difficult to weigh them in the wild. Most adult male hippos weigh between . Females hippos are smaller and usually weigh between . Older males can get even bigger. They are at least and sometimes even weigh .


title: Hippopotamus

text: Male hippos seem to keep on growing for their whole lives. Females hippos, though, become the heaviest when they are about 25 years old.


title: Hippopotamus

text: Hippos have big and heavy bodies, dark gray skin and short legs. A hippo's main defence is their extremely strong mouth. They can grow to be 15 feet long and weigh 3,000 pounds.


title: Hippopotamus

text: Hippopotami are herbivores which live in groups. Despite being semiaquatic and having webbed feet, an adult hippo is not a particularly good swimmer nor can it float. It is rarely found in deep water; when it is, the animal moves by porpoise-like leaps from the bottom. They usually stay in the mud and water during the day and come out to eat grass or leaves at night. Though they are bulky animals, hippopotami can gallop at 30 km/h (19 mph) on land but normally trot.


title: Hippopotamus

text: Many hippos lived in North Africa and Europe until about 30,000 years ago. They used to be common in Egypt's Nile region from long ago, though they are not there now. Pliny the Elder writes that, in his time, the best place in Egypt for finding this animal was in Sais. The animal could still be found around there after the Arab Conquest in 639. Hippos are still found in the rivers and lakes of: Uganda, Sudan, Somalia, Kenya, northern Democratic Republic of the Congo and Ethiopia, west through Ghana to Gambia and also in Southern Africa (Botswana, Republic of South Africa, Zimbabwe, Zambia). Some hippos also live in Tanzania and Mozambique. They like to live in places with water that is not too deep.


title: Hippopotamus

text: Hippos are very aggressive towards humans, whom they commonly attack whether in boats or on land with no apparent provocation. This aggression by the hippopotamus is caused by humans coming too close to their children. Hippopotami are very protective of their young and they often fear that humans pose a large threat to their young. They are widely considered to be one of the most dangerous large animals in Africa.


title: Hippopotamus

text: The earliest proof that humans were involved with hippos comes from butchery cut marks on hippo bones at Bouri Formation from around 160,000 years ago. Later rock paintings and engravings showing hippos being hunted. They have been found in the mountains of the central Sahara from 4,000–5,000 years ago near Djanet. Ancient Egyptians also knew much about hippos. They knew the hippo was a fierce, wild animal that lived in the Nile. In Egyptian mythology, Tawaret, a goddess of protection in pregnancy and childbirth, had the head of a hippo. This was because ancient Egyptians saw how protective female hippopotami could be about their young.


title: Delaware

text: Delaware () is a state in the United States. It is sometimes called the "First State" because it was the first colony to accept the new constitution in 1787. Its capital is Dover and its biggest city is Wilmington. It is the second smallest state in the United States.


title: Delaware

text: Delaware is long and ranges from to across, totaling , making it the second-smallest state in the United States after Rhode Island. Delaware is bounded to the north by Pennsylvania; to the east by the Delaware River, Delaware Bay, New Jersey and the Atlantic Ocean; and to the west and south by Maryland.


title: Delaware

text: Delaware is on a level plain, with the lowest mean elevation of any state in the nation. Its highest elevation, located at Ebright Azimuth, near Concord High School, is less than above sea level.


title: Delaware

text: The transitional climate of Delaware supports a wide variety of vegetation. In the northern third of the state are found Northeastern coastal forests and mixed oak forests typical of the northeastern United States. In the southern two-thirds of the state are found Middle Atlantic coastal forests. Trap Pond State Park, along with areas in other parts of Sussex County, for example, support the northernmost stands of bald cypress trees in North America.


title: Delaware

text: Delaware provides government subsidy support for the clean-up of property "lightly contaminated" by hazardous waste, the proceeds for which come from a tax on wholesale petroleum sales.


title: Parts of a sail

text: There are two types of common mainsails. The Three Sided Mainsail and the Four sided Mainsail. Each of these Mainsail types have many different names according to exact location and relationship of supporting spars.


title: Parts of a sail

text: The headsail of a sailboat is any sail set forward of the mast (on a single masted boat) or foremast (the mast nearest the bow). The corresponding parts are the same relative to the front of the boat. (Note: The headsail tack is the name for the lower corner of the headsail -- the sail closest to the front of the boat.)


title: Slide rule

text: The slide rule, or "slipstick", is a mechanical analog computer. The slide rule is used mainly for multiplication and division, and also for "scientific" functions such as roots, logarithms and trigonometry, but usually not for addition or subtraction.


title: Slide rule

text: There are many different styles of slide rules. They are usually linear or circular. They have a standardised set of markings or scales. These scales are used for mathematical computations. Some slide rules have been made for special use, as for aviation or finance. Those slide rules have special scales for those applications, as well as normal scales.


title: Slide rule

text: The slide rule is based on the work on logarithms by John Napier and was invented by William Oughtred. Before electronic calculators were developed, slide rules were the tool used most often in science and engineering. The use of slide rules continued to grow through the 1950s and 1960s even as digital computing devices were gradually introduced; but around 1974 the pocket calculator made the slide rule largely obsolete and most suppliers left the business.


title: Slide rule

text: In its most basic form, the slide rule uses two logarithmic scales to allow rapid multiplication and division of numbers. These common operations can be time-consuming and error-prone when done on paper. More complex slide rules allow other calculations, such as square roots, exponentials, logarithms, and trigonometric functions.


title: Slide rule

text: Mathematical calculations are done by aligning a mark on the sliding central strip with one on one of the fixed strips.


title: Slide rule

text: The relative position of other marks can then be observed. Numbers aligned with the marks give the approximate value of the product, quotient, or other calculated result.


title: Slide rule

text: The user determines the location of the decimal point in the result, based on mental estimation. Scientific notation is used to track the decimal point in more formal calculations. Addition and subtraction steps in a calculation are generally done mentally or on paper, not on the slide rule.


title: Slide rule

text: Most slide rules have three linear strips of the same length. The strips are aligned in parallel and interlocked so that the central strip can be moved lengthwise relative to the other two. The outer two strips are fixed so that their relative positions do not change.


title: Slide rule

text: Some slide rules ("duplex" models) have scales on both sides of the rule and slide strip, others on one side of the outer strips and both sides of the slide strip, still others on one side only ("simplex" rules). A sliding cursor with a vertical alignment line is used to find corresponding points on scales that are not next to each other or, in duplex models, are on the other side of the rule. The cursor can also record an intermediate result on any of the scales.


title: Slide rule

text: A logarithm transforms the operations of multiplication and division to addition and subtraction according to the rules formula_1 and formula_2.


title: Slide rule

text: Moving the top scale to the right by a distance of formula_3, by matching the beginning of the top scale with the label formula_4 on the bottom, aligns each number formula_5, at position formula_6 on the top scale, with the number at position formula_7 on the bottom scale. Because formula_8, this position on the bottom scale gives formula_9, the product of formula_4 and formula_5. For example, to calculate 3 × 2 (represented as 3*2 on a calculator), the 1 on the top scale is moved to the 2 on the bottom scale. The answer, 6, is read off the bottom scale where 3 is on the top scale. In general, the 1 on the top is moved to a factor on the bottom, and the answer is read off the bottom where the other factor is on the top.


title: Slide rule

text: Operations may go "off the scale;" for example, the diagram above shows that the slide rule has not positioned the 7 on the upper scale above any number on the lower scale, so it does not give any answer for 2×7. In such cases, the user may slide the upper scale to the left until its right index aligns with the 2, effectively multiplying by 0.2 instead of by 2, as in the illustration below:


title: Slide rule

text: Here the user of the slide rule must remember to adjust the decimal point appropriately to correct the final answer. We wanted to find 2×7, but instead we calculated 0.2×7=1.4. So the true answer is not 1.4 but 14. Resetting the slide is not the only way to handle multiplications that would result in off-scale results, such as 2×7; some other methods are:


title: Slide rule

text: Method 1 is easy to understand, but entails a loss of precision. Method 3 has the advantage that it only involves two scales.


title: Slide rule

text: The illustration below demonstrates the computation of 5.5/2. The 2 on the top scale is placed over the 5.5 on the bottom scale. The 1 on the top scale lies above the quotient, 2.75. There is more than one method for doing division, but the method presented here has the advantage that the final result cannot be off-scale, because one has a choice of using the 1 at either end.


title: Slide rule

text: In addition to the logarithmic scales, some slide rules have other mathematical functions encoded on other auxiliary scales. The most popular were trigonometric, usually sine and tangent, common logarithm (log) (for taking the log of a value on a multiplier scale), natural logarithm (ln) and exponential ("e") scales. Some rules include a Pythagorean scale, to figure sides of triangles, and a scale to figure circles. Others feature scales for calculating hyperbolic functions. On linear rules, the scales and their labeling are highly standardized, with variation usually occurring only in terms of which scales are included and in what order:


title: Slide rule

text: The Binary Slide Rule manufactured by Gilson in 1931 performed an addition and subtraction function limited to fractions.


title: Slide rule

text: There are single-decade (C and D), double-decade (A and B), and triple-decade (K) scales. To compute formula_12, for example, locate x on the D scale and read its square on the A scale. Inverting this process allows square roots to be found, and similarly for the powers 3, 1/3, 2/3, and 3/2. Care must be taken when the base, x, is found in more than one place on its scale. For instance, there are two nines on the A scale; to find the square root of nine, use the first one; the second one gives the square root of 90.


title: Slide rule

text: For formula_13 problems, use the LL scales. When several LL scales are present, use the one with x on it. First, align the leftmost 1 on the C scale with x on the LL scale. Then, find y on the C scale and go down to the LL scale with x on it. That scale will indicate the answer. If y is "off the scale," locate formula_14 and square it using the A and B scales as described above.


title: Slide rule

text: The S, T, and ST scales are used for trigonometric functions and multiples of trig functions, for angles in degrees. Many slide rules have their S, T, and ST scales marked with degrees and minutes. So-called "decitrig" models use decimal fractions of degrees instead.


title: Slide rule

text: Base-10 logarithms and exponentials are found using the L scale, which is linear. Some slide rules have a Ln scale, which is for base e.


title: Slide rule

text: The Ln scale was invented by an 11th grade student, Stephen B. Cohen, in 1958. The original intent was to allow the user to select an exponent "x" (in the range 0 to 2.3) on the Ln scale and read e on the C (or D) scale and e on the CI (or DI) scale. Pickett, Inc. was given exclusive rights to the scale. Later, the inventor created a set of "marks" on the Ln scale to extend the range beyond the 2.3 limit, but Pickett never incorporated these marks on any of its slide rules.


title: Slide rule

text: Slide rules are not typically used for addition and subtraction, but it is nevertheless possible to do so using two different techniques.


title: Slide rule

text: The first method to perform addition and subtraction on the C and D (or any comparable scales) requires converting the problem into one of division. For addition, the quotient of the two variables plus one times the divisor equals their sum:


title: Slide rule

text: For subtraction, the quotient of the two variables minus one times the divisor equals their difference:


title: Slide rule

text: This method is similar to the addition/subtraction technique used for high-speed electronic circuits with the logarithmic number system in specialized computer applications like the Gravity Pipe (GRAPE) supercomputer and hidden Markov models.


title: Slide rule

text: The second method uses a sliding linear L scale available on some models. Addition and subtraction are performed by sliding the cursor left (for subtraction) or right (for addition) then returning the slide to 0 to read the result.


title: Slide rule

text: The length of the slide rule is quoted in terms of the nominal length of the scales. Scales on the most common "10-inch" models are actually 25 cm in length, as they were made to metric standards, though some rules offer slightly extended scales to simplify manipulation when a result overflowed. Pocket rules are typically 5 inches. Models a couple of meters long were sold to be hung in classrooms for teaching purposes.


title: Slide rule

text: Typically the divisions mark a scale to a precision of two significant figures, and the user estimates the third figure. Some high-end slide rules have magnifying cursors that make the markings easier to see. Such cursors can effectively double the accuracy of readings, permitting a 10-inch slide rule to serve as well as a 20-inch.


title: Slide rule

text: Various other conveniences have been developed. Trigonometric scales are sometimes dual-labeled, in black and red, with complementary angles, the so-called "Darmstadt" style. Duplex slide rules often duplicate some of the scales on the back. Scales are often "split" to get higher accuracy.


title: Slide rule

text: Specialized slide rules were invented for various forms of engineering, business and banking. These often had common calculations directly expressed as special scales, for example loan calculations, optimal purchase quantities, or particular engineering equations. For example, the Fisher Controls company distributed a customized slide rule adapted to solving the equations used for selecting the proper size of industrial flow control valves.


title: Slide rule

text: Circular slide rules come in two basic types, one with two cursors (left), and another with a movable disk and a single cursor (right). The dual cursor versions perform multiplication and division by maintaining a fixed angle between the cursors as they are rotated around the dial. The single cursor version operates more like the standard slide rule through the appropriate alignment of the scales.


title: Slide rule

text: The basic advantage of a circular slide rule is that the longest dimension of the tool was reduced by a factor of about 3 (i.e. by π). For example, the outer scale of a 10 cm circular would have a maximum precision equal to a 30 cm ordinary slide rule. Circular slide rules also eliminate "off-scale" calculations, because the scales were designed to "wrap around"; they never have to be re-oriented when results are near 1.0—the rule is always on scale. However, for non-cyclical non-spiral scales such as S, T, and LL's, the scale length is shortened to make room for end margins.


title: Slide rule

text: Circular slide rules are mechanically more rugged and smoother-moving, but their scale alignment precision is sensitive to the centering of a central pivot; a minute 0.1 mm off-centre of the pivot can result in a 0.2 mm worst case alignment error. The pivot, however, does prevent scratching of the face and cursors. The highest accuracy scales are placed on the outer rings. Rather than "split" scales, high-end circular rules use spiral scales for more complex operations like log-of-log scales. One eight-inch premium circular rule had a 50-inch spiral log-log scale.


title: Slide rule

text: The main disadvantages of circular slide rules are the difficulty in locating figures along a rotating disc, and limited number of scales. Another drawback of circular slide rules is that less-important scales are closer to the center, and have lower precisions. Most students learned slide rule use on the linear slide rules, and did not find reason to switch.


title: Slide rule

text: One slide rule remaining in daily use around the world is the E6B. This is a circular slide rule first created in the 1930s for aircraft pilots to help with dead reckoning. With the aid of scales printed on the frame it also helps with such miscellaneous tasks as converting time, distance, speed, and temperature values, compass errors, and calculating fuel use. The so-called "prayer wheel" is still available in flight shops, and remains widely used. While GPS has reduced the use of dead reckoning for aerial navigation, and handheld calculators have taken over many of its functions, the E6B remains widely used as a primary or backup device and the majority of flight schools demand that their students have some degree of its mastery.


title: Slide rule

text: In 1952, Swiss watch company Breitling introduced a pilot's wristwatch with an integrated circular slide rule specialized for flight calculations: the Breitling Navitimer. The Navitimer circular rule, referred to by Breitling as a "navigation computer", featured airspeed, rate/time of climb/descent, flight time, distance, and fuel consumption functions, as well as kilometer–nautical mile and gallon–liter fuel amount conversion functions.


title: Slide rule

text: Traditionally slide rules were made out of hard wood such as mahogany or boxwood with cursors of glass and metal. At least one high precision instrument was made of steel.


title: Slide rule

text: In 1895, a Japanese firm, Hemmi, started to make slide rules from bamboo, which had the advantages of being dimensionally stable, strong and naturally self-lubricating. These bamboo slide rules were introduced in Sweden in September, 1933 , and probably only a little earlier in Germany. Scales were made of celluloid or plastic. Later slide rules were made of plastic, or aluminum painted with plastic. Later cursors were acrylics or polycarbonates sliding on Teflon bearings.


title: Slide rule

text: All premium slide rules had numbers and scales engraved, and then filled with paint or other resin. Painted or imprinted slide rules were viewed as inferior because the markings could wear off. Nevertheless, Pickett, probably America's most successful slide rule company, made all printed scales. Premium slide rules included clever catches so the rule would not fall apart by accident, and bumpers to protect the scales and cursor from rubbing on tabletops. The recommended cleaning method for engraved markings is to scrub lightly with steel-wool. For painted slide rules, and the faint of heart, use diluted commercial window-cleaning fluid and a soft cloth.


title: Slide rule

text: The slide rule was invented around 1620–1630, shortly after John Napier's publication of the concept of the logarithm. Edmund Gunter of Oxford developed a calculating device with a single logarithmic scale, which, with additional measuring tools, could be used to multiply and divide. The first description of this scale was published in Paris in 1624 by Edmund Wingate (c. 1593 – 1656), an English mathematician, in a book entitled "“L'usage de la reigle de proportion en l'arithmetique & geometrie”." The book contains a double scale on one side of which is a logarithmic scale and on the other a tabular scale. In 1630, William Oughtred of Cambridge invented a circular slide rule, and in 1632 he combined two Gunter rules, held together with the hands, to make a device that is recognizably the modern slide rule. Like his contemporary at Cambridge, Isaac Newton, Oughtred taught his ideas privately to his students, but delayed in publishing them, and like Newton, he became involved in a vitriolic controversy over priority, with his one-time student Richard Delamain and the prior claims of Wingate. Oughtred's ideas were only made public in publications of his student William Forster in 1632 and 1653.


title: Slide rule

text: In 1677, Henry Coggeshall created a two-foot folding rule for timber measure, called the Coggeshall slide rule. His design and uses for the tool gave the slide rule purpose outside of mathematical inquiry.


title: Slide rule

text: In 1722, Warner introduced the two- and three-decade scales, and in 1755 Everard included an inverted scale; a slide rule containing all of these scales is usually known as a "polyphase" rule.


title: Slide rule

text: In 1815, Peter Roget invented the log log slide rule, which included a scale displaying the logarithm of the logarithm. This allowed the user to directly perform calculations involving roots and exponents. This was especially useful for fractional powers.


title: Slide rule

text: The more modern form was created in 1859 by French artillery lieutenant Amédée Mannheim, "who was fortunate in having his rule made by a firm of national reputation and in having it adopted by the French Artillery." It was around that time, as engineering became a recognized professional activity, that slide rules came into wide use in Europe. They did not become common in the United States until 1881, when Edwin Thacher introduced a cylindrical rule there. The duplex rule was invented by William Cox in 1891, and was produced by Keuffel and Esser Co. of New York.


title: Slide rule

text: Astronomical work also required fine computations, and in 19th century Germany a steel slide rule about 2 meters long was used at one observatory. It had a microscope attached, giving it accuracy to six decimal places.


title: Slide rule

text: In World War II, bombardiers and navigators who required quick calculations often used specialized slide rules. One office of the U.S. Navy actually designed a generic slide rule "chassis" with an aluminum body and plastic cursor into which celluloid cards (printed on both sides) could be placed for special calculations. The process was invented to calculate range, fuel use and altitude for aircraft, and then adapted to many other purposes.


title: Slide rule

text: Throughout the 1950s and 1960s the slide rule was the symbol of the engineer's profession (in the same way that the stethoscope symbolizes the medical profession). German rocket scientist Wernher von Braun brought two 1930s vintage "Nestler" slide rules with him when he moved to the U.S. after World War II to work on the American space program. Throughout his life he never used any other pocket calculating devices; slide rules served him perfectly well for making quick estimates of rocket design parameters and other figures. Aluminum Pickett-brand slide rules were carried on five Apollo space missions, including to the moon, according to advertising on Pickett's N600 slide rule boxes .


title: Slide rule

text: Some engineering students and engineers carried ten-inch slide rules in belt holsters, and even into the mid 1970s this was a common sight on campuses. Students also might keep a ten-or twenty-inch rule for precision work at home or the office while carrying a five-inch pocket slide rule around with them.


title: Slide rule

text: In 2004, education researchers David B. Sher and Dean C. Nataro conceived a new type of slide rule based on "prosthaphaeresis", an algorithm for rapidly computing products that predates logarithms. There has been little practical interest in constructing one beyond the initial prototype, however.


title: Slide rule

text: The importance of the slide rule began to diminish as electronic computers, a new but very scarce resource in the 1950s, became widely available to technical workers during the 1960s. The introduction of Fortran in 1957 made computers practical for solving modest size mathematical problems. IBM introduced a series of more affordable computers, the IBM 650 (1954), IBM 1620 (1959), IBM 1130 (1965) addressed to the science and engineering market. John Kemeny's BASIC programming language (1964) made it easy for students to use computers. The DEC PDP-8 minicomputer was introduced in 1965.


title: Slide rule

text: Computers also changed the nature of calculation. With slide rules, there was a great emphasis on working the algebra to get expressions into the most computable form. Users of slide rules would simply approximate or drop small terms to simplify the calculation. Fortran allowed complicated formulas to be typed in from textbooks without the effort of reformulation. Numerical integration was often easier than trying to find closed form solutions for difficult problems. The young engineer asking for computer time to solve a problem that could have been done by a few swipes on the slide rule became a humorous cliché. Many computer centers had a framed slide rule hung on a wall with the note "In case of emergency, break glass."


title: Slide rule

text: Another step toward the replacement of slide rules with electronics was the development of electronic calculators for scientific and engineering use. The first included the Wang Laboratories LOCI-2, introduced in 1965, which used logarithms for multiplication and division and the Hewlett-Packard HP-9100, introduced in 1968. The HP-9100 had trigonometric functions (sin, cos, tan) in addition to exponentials and logarithms. It used the CORDIC (coordinate rotation digital computer) algorithm, which allows for calculation of trigonometric functions using only shift and add operations. This method facilitated the development of ever smaller scientific calculators.


title: Slide rule

text: The last nail in the coffin for the slide rule was the launch of pocket-sized scientific calculators, of which the 1972 Hewlett-Packard HP-35 was the first. Such calculators became known as "slide rule" calculators since they could perform most or all of the functions on a slide rule. At several hundred dollars, even this was considered expensive for most students. While professional slide rules could also be quite expensive, drug stores often sold basic plastic models for under $20 USD. But by 1975, basic four-function electronic calculators could be purchased for under $50. By 1976 the TI-30 offered a scientific calculator for under $25. After this time, the market for slide rules dried up quickly as small scientific calculators became affordable.


title: Slide rule

text: One advantage of using a slide rule together with an electronic calculator is that an important calculation can be checked by doing it on both; because the two instruments are so different, there is little chance of making the same mistake twice.


title: Nanga Parbat

text: Nanga Parbat is a mountain in Gilgit-Baltistan, between Chilas and Astore. It is the ninth highest mountain in the world. It is above sea level. Nanga Parbat means "Naked Mountain". In 1953, an Austrian German named Hermann Buhl was the first to climb it.


title: Nanga Parbat

text: Nanga Parbat is in the west of the Himalayas, and is the most western of the mountains higher than eight thousand meters. It lies just south of the Indus River, in the Astore District of the Northern Areas in the region of Kashmir. Not far to the north is the western end of the Karakoram mountains.


title: Nanga Parbat

text: Nanga Parbat is the highest peak in the Nanga Parbat Range. The range covers an area of in length and in width. In the east it joins the Pir Panjal Range.


title: Nanga Parbat

text: The steep incline of its peak that rises above the ground far below makes Nanga Parbat a difficult and dangerous climb. Many deaths in the mid and early 20th century gave it the nickname of "killer mountain".


title: Carbon steel

text: Carbon steel or plain-carbon steel, is a metal alloy. It is a combination of two elements, iron and carbon. Other elements are present in quantities too small to affect its properties. The only other elements allowed in plain-carbon steel are: manganese (1.65% max), silicon (0.60% max), and copper (0.60% max). Steel with a low carbon content has the same properties as iron, soft but easily formed. With more carbon the metal gains hardness and strength but becomes less ductile and more difficult to weld. Higher carbon content lowers steel's melting point and its temperature resistance in general.


title: Carbon steel

text: Steel can be heat-treated which allows parts to be fabricated in an easily fordable soft state. If enough carbon is present, the alloy can be hardened to increase strength, wear, and impact resistance. Steels are often wrought by cold-working methods, which is the shaping of metal through deformation at a low equilibrium or meta stable temperature.


title: Carbon steel

text: Mild steel is the most common form of steel as its price is relatively low while it provides material properties that are acceptable for many applications. Mild steel has a low carbon content (up to 0.3%) and is therefore neither extremely brittle nor ductile. It becomes malleable when heated, and so can be forged. It is also often used where large amounts of steel need to be formed, for example as structural steel. Density of this metal is 7861.093 kg/m³ (0.284 lb/in³) and the tensile strength is a maximum of 500 MPa (72500 psi)


title: Carbon steel

text: Carbon steels which can successfully undergo heat-treatment have a carbon content in the range of 0.30% to 1.70% by weight. Trace impurities of various other elements can have a significant effect on the quality of the resulting steel. Trace amounts of sulfur make the steel "red-short", which is a fault: the steel is brittle and crumbly. Low alloy carbon steel, such as A36 grade, contains about 0.05% sulfur and melts around 1426–1538 °C (2600–2800 °F). Manganese is often added to improve the hardenability of low carbon steels. These additions turn the material into a low alloy steel by some definitions, but AISI's definition of carbon steel allows up to 1.65% manganese by weight.


title: Carbon steel

text: Silver Steel or high-carbon bright steel, gets its name from its appearance, due to the high carbon content. It is a very-high carbon steel, or can be thought of as some of the best high-carbon steel. It is defined under the steel specification standards BS-1407. It is a 1% carbon tool steel which can be ground to close tolerances. Usually the range of carbon is minimum 1.10% but as high as 1.20%. It also contains trace elements of 0.35% Mn (range 0.30%-0.40%), 0.40% Cr (range 0.4%-0.5%), 0.30% Si (range 0.1%-0.3%), and also sometimes sulfur (max 0.035%) and phosphorus (max 0.035%). Silver steel is sometimes used for making straight razors, due to its ability to produce and hold a micro-fine edge.


title: Carbon steel

text: The purpose of heat treating plain-carbon steel is to change the mechanical properties of steel, usually ductility, hardness, yield strength, and impact resistance.


title: B

text: B is the 2nd letter of the English alphabet. Its appearance depends on the writer's calligraphy. It has an uppercase and lowercase version like any other letters.


title: B

text: The letter B was already part of the Phoenician alphabet more than 3000 years ago in 1000 BCE. It's part of many alphabets today.


title: Broadcasting

text: In communications, such as radio and television, broadcasting means sending information such as television shows or music electronically to a large audience. The information is sent through the air in radio waves, through a wire, or by a communications satellite, and then the television viewers or radio listeners pick up the signal using their television sets and radio receivers. Gugliemo Marconi invented wireless telegraphy, in December 1901 he transmitted first radio signals across the Atlantic Ocean. This was point to point. Experiments with voice broadcasting began a few years later, and it grew rapidly in the 1920s.


title: Broadcasting

text: Different broadcasters use different radio waves and different modulating methods. amplitude modulation on medium waves was the first to be much used.


title: Broadcasting

text: Some television networks are said to be broadcasting, even if they are only or mainly on cable TV rather than by radio waves.


title: Broadcasting

text: Many countries have Public broadcasting, using money from the government to broadcast television shows and radio programs. Examples include the BBC in Britain, NHK in Japan, and the CBC in Canada.


title: Broadcasting

text: In the United States, most public broadcast radio and television stations are run by educational groups (such as colleges or universities) or by a state's educational department. Public broadcasters, by law, cannot accept or display commercial advertising. However, businesses can make donations to a public broadcaster. Most are part of the Public Broadcasting System.


title: Broadcasting

text: PBS is different than the other public broadcasters such as BBC, NHK and CBC, because the PBS gets a lot of its funding (money) from donations by viewers and listeners. Public broadcasters make programs that the private companies are not interested in making, such as educational children's shows, documentaries, and public affairs shows about current issues.


title: Broadcasting

text: As well, there are private broadcasting companies. These are companies that broadcast television and radio programs. To make money, private broadcasting companies sell advertisements called commercials.


title: Broadcasting

text: A third type of broadcaster is community broadcasters. There are community television stations and community radio stations.


title: Broadcasting

text: Community television stations are often provided on cable networks. Community television stations usually have shows about local issues and community events. Some community television stations film and broadcast community cultural activities, such as musical performances or town hall meetings.


title: Broadcasting

text: Community radio stations play music and have public affairs shows about community issues. Community radio stations are usually small organizations that are run by volunteers. Community radio stations often get their funding (money) from local governments, local universities, and from donations by listeners. Some community radio stations also have poetry readings by local poets, or performances by local musicians or singers.


title: Broadcasting

text: Broadcasting can also mean sending a message to many users on a computer network at exactly the same time, or sending a message from one computer to many other computers, giving information about itself, such as its name and location.


title: Justin Trudeau

text: Justin Pierre James Trudeau (born December 25, 1971) is a Canadian politician. He is the 23rd and current Prime Minister of Canada. He is also the leader of the Liberal Party of Canada. He was elected leader on April 14, 2013. After leading his party to a majority government win in the 2015 federal election, Trudeau became the Prime Minister. Since 2021, Trudeau is the senior G7 leader.


title: Justin Trudeau

text: Trudeau is the eldest son of former Prime Minister Pierre Trudeau. He is the second child in Canadian history to be born while one of his parents was prime minister; the first was John A. Macdonald's youngest daughter Margaret Mary Macdonald.


title: Justin Trudeau

text: Trudeau earned a Bachelor of Arts degree in literature from McGill University and a Bachelor of Education degree from the University of British Columbia. After he graduated, Trudeau worked as a social studies, drama, math and French elementary and high school teacher. He taught at West Point Grey Academy and Sir Winston Churchill Secondary School in Vancouver, British Columbia.


title: Justin Trudeau

text: Trudeau was elected for the first time in the 2008 federal election. He was the nominee for the Liberal Party in the electoral area of Papineau. He won more votes than the incumbent, Vivian Barbot of the Bloc Québécois.


title: Justin Trudeau

text: On October 19, 2015, Trudeau and the Liberals won the most seats in the federal election. This was after one of the longest campaigns in over 100 years. The Liberals won 184 of the 338 seats in the House of Commons and 39.5% of the total vote. Because of this, they formed a majority government. Their seat count went up by 150 compared to the 2011 federal election.


title: Justin Trudeau

text: The results were the second-best in the history of the Liberal Party. They did very well in the eastern half of Canada. They won all of the seats in Atlantic Canada and Toronto and won 40 seats in Quebec. In Quebec, they won the most seats since Pierre Trudeau's win in the 1980 election. It was also the first time since 1980 that the Liberals won more than half the seats in Quebec. The 150 seat gain was the biggest gain for any party in an election since Canadian Confederation. It was also the first time that a party went from third place in seat count to a majority government.


title: Justin Trudeau

text: Trudeau and the Cabinet he chose were sworn in by the Governor General David Johnston on November 4, 2015.


title: Justin Trudeau

text: In 2022, he invoked the Emergencies Act in response to the Freedom Convoy protests, the first time the act was brought into force since it was enacted in 1988.


title: Justin Trudeau

text: Trudeau visited the Governor General, Julie Payette on September 11, 2019. This was to ask that Parliament be dissolved and new elections would begin.


title: Justin Trudeau

text: For the first time since 1979, the party that won the largest share of the national popular vote did not win the most seats. The Liberals under Trudeau had 33.1 per cent of the popular vote, while the Conservatives under Andrew Scheer had 34.4 per cent. It was also the first time a government took power with less than 35 per cent of the national popular vote since 1867.


title: Justin Trudeau

text: On September 20, 2021 Trudeau and the Liberal Party won re-election as the party won 160 seats, allowing them to form a minority government.


title: Justin Trudeau

text: Trudeau first met his wife, Sophie Grégoire, when they were both children growing up in Montreal. Grégoire was a friend of Trudeau's brother, Michel. He married her on May 28, 2005 in a Catholic wedding at the Sainte-Madeleine d'Outremont Church in Montreal. They have three children together: a son, Xavier James Trudeau (born October 18, 2007), a daughter, Ella-Grace Margaret Trudeau (born February 5, 2009), and another son, Hadrien Grégoire Trudeau (born February 28, 2014).


title: Justin Trudeau

text: On March 12, 2020, Trudeau and his wife Sophie Grégoire Trudeau isolated themselves, after she showed flu-like symptoms during the 2019–20 coronavirus pandemic. The Prime Minister's Office announced later that day that she had tested positive for COVID-19.


title: Native speaker

text: A native speaker is someone who learned to speak a language as part of their childhood development. A native speaker's language is usually the language their parents speak and/or the language of their country of origin. It is the only language of a monolingual person, and likely the first language of a multilingual person which is acquired naturally in their native environment. It may serve as the basis for their sociolinguistic identity.


title: Covalent bond

text: A covalent bond is a chemical bond between two non-metal atoms. An example is water, where hydrogen (H) and oxygen (O) bond together to make (HO). A full outer shell usually has eight electrons, or two in the case of hydrogen or helium. Valence electrons are the electrons held comparatively loosely in the outer shell of the atom. (The structure of electron shells is determined by quantum mechanics.)


title: Covalent bond

text: The number of electrons in an atom is decided by the number of protons in the atom. Electrons orbit atomic nuclei, and they are like fuzzy orbital paths around an atomic nucleus. The first layer has up to two electrons. The layers after that usually contain up to eight. Covalent bonds are formed by atoms sharing valence electrons.


title: Covalent bond

text: If for example, an atom had nine electrons, the first two orbit very close to the nucleus, the next seven orbit a little farther away. The outer seven electrons are less tightly held than the inner two electrons because they are further away from the positively charged nucleus. If this atom gets close to another atom, with a loosely held electron in its outer shell, a new orbital will become available to the loosely held electron. This new electron orbital is bound to both atomic nuclei and has a lower energy level than the original electron orbital. The electron can spontaneously jump to it and emit a photon with the excess energy. Now we have an electron orbiting both atoms which results in the atom that provided the electron having a small net positive charge and the other atom having a small net negative charge. The two atoms are now held together by the electromagnetic force of attraction between positive and negative charges. This is called a covalent bond. To break this bond needs the same amount of energy as was released when it was formed.


title: Covalent bond

text: A water molecule consists of one oxygen atom and two hydrogen atoms held together by a covalent bond. In this case the oxygen atom shares one electron with each hydrogen atom. This means that the oxygen atoms has a small net positive charge and the hydrogen atom has a small net negative charge. As a result, the oxygen and hydrogen atoms are attracted to each other due to the electromagnetic force. Because of this the water molecule is a polar molecule: its charge is not evenly distributed.


title: Covalent bond

text: Covalent bonds are weaker than ionic bonds, and have a lower melting point. They are also generally poor conductors of electricity and heat.


title: Covalent bond

text: In chemistry, bond length is the measure of the size of a covalent bond. Because molecules are very small, they are measured in picometers, or about one millionth of a billionth of a meter.


title: Covalent bond

text: The chemistry of molecules is explained mostly by their bonds, and their bonds are caused by their structure of electrons.


title: Ethiopia

text: Ethiopia (, , , , Oromo: Itiyophiyaa, , Tigrinya: ኢትዮጵያ) is a country in the Horn of Africa. It has one of the longest and most well known histories as a country in Africa and the world. Ethiopia was one of the few countries in Africa that escaped the Scramble for Africa. It avoided being colonized until 1935, when it was invaded by the Italians under Benito Mussolini, who took over the country for a brief time. Ethiopia used to be called Abyssinia. The word "Ethiopia" is from the Greek word Αἰθιοπία (IPA: /ˌaitʰioˈpia/) meaning sun light burned face. It is the most populous landlocked country in the world. It lost its Red Sea ports when Eritrea gained independence in 1993.


title: Ethiopia

text: The idea of an Ethiopian nation became important with the Kingdom of Aksum in the 4th century A.D. The Aksumite Kingdom was a mainly Christian state that at its biggest controlled what is now the Ethiopian Highlands, Eritrea, and the coastal regions of Southern Arabia. The Aksumite Kingdom was responsible for the development of the religious movement that became the Ethiopian Orthodox Tewahedo Church. However, the expansion of Islam in the 7th century caused the decline of the Aksumite Kingdom, and most of the lowland populations converted to Islam, while the highland people remained Christian. Since the Aksumite people became divided between Christian highlands and Islamic lowlands, religious and tribal tensions and rivalries between the people intensified. The Aksumite society changed into a loose confederation of city-states that maintained traditions and languages influenced by Aksum.


title: Ethiopia

text: After the fall of Aksum due to declining sea trade from fierce competition by Muslims and changing climate, the power base of the kingdom migrated south and shifted its capital to Kubar (near Agew). They moved southwards because, even though the Axumite Kingdom welcomed and protected the companions of Prophet Muhammad to Ethiopia, who came as refugees to escape the persecution of the ruling families of Mecca and earned the friendship and respect of the Prophet. Their friendship deteriorated when South-Arabians invaded the Dahlak islands through the port of Adulis and destroyed it, which was the economic backbone for the prosperous Aksumite Kingdom. After a second golden age in the early 6th century the Aksumite empire began to decline in the mid 6th century, eventually ceasing its production of coins in the early 7th century. Around this same time, the Aksumite population was forced to go farther inland to the highlands for protection, abandoning Aksum as the capital. Arab writers of the time continued to describe Ethiopia (no longer referred to as Aksum) as an extensive and powerful state, though they had lost control of most of the coast and their tributaries. While land was lost in the north, it was gained in the south; and, though Ethiopia was no longer an economic power, it still attracted Arab merchants. The capital was moved to a new location, currently unknown, though it may have been called Ku'bar or Jarmi.


title: Ethiopia

text: Under the reign of Degna Djan, during the 10th century, the empire kept expanding south, and sent troops into the modern-day region of Kaffa, while at the same time undertaking missionary activity into Angot and Amhara.


title: Ethiopia

text: Local history holds that, around 960, a Jewish Queen named Yodit (Judith) or "Gudit" defeated the empire and burned its churches and literature. While there is evidence of churches being burned and an invasion around this time, her existence has been questioned by some western authors. Another possibility is that the Aksumite power was ended by a southern pagan queen named Bani al-Hamwiyah, possibly of the tribe al-Damutah or Damoti of the Sidama people. It is clear from contemporary sources that a female usurper did indeed rule the country at this time, and that her reign ended some time before 1003. After a short Dark Age, the Aksumite Empire was succeeded by the Agaw Zagwe dynasty in the 11th or 12th century (most likely around 1137), although limited in size and scope. However, Yekuno Amlak, who killed the last Zagwe king and founded the modern Solomonic dynasty around 1270 traced his ancestry and his right to rule from the last emperor of Aksum, Dil Na'od. It should be mentioned that the end of the Aksumite Empire didn't mean the end of Aksumite culture and traditions; for example, the architecture of the Zagwe dynasty at Lalibela and Yemrehana Krestos Church shows heavy Aksumite influence.


title: Ethiopia

text: Fearing of what recently occurred, Axum shifted its capital near Agew In the middle of the sixteenth century Adal Sultanate armies led by Harar leader Ahmed Gragn invaded the Ethiopian Highlands in what is known as the ""Conquest of Habasha"". Following Gragn invasions the southern part of the Empire was lost to Ethiopia and scattered several groups like the Gurage people were cut off from the rest of Abyssinia. In the late sixteenth century the nomadic Oromo people penetrated the Abyssinian plains occupying large territories during the Oromo migrations. Abyssinian warlords often competed with each other for dominance of the realm. The Amharas seemed to gain the upper hand with the accession of Yekuno Amlak of Ancient Bete Amhara in 1270, after defeating the Agaw lords of Lasta.


title: Ethiopia

text: The Gondarian dynasty, which since the 16th century had become the centre of Royal pomp and ceremony of Abyssinia, finally lost its influence as a result of the emergence of powerful regional lords, following the murder of Iyasu I, also known as Iyasu the Great. The decline in the prestige of the dynasty led to the semi-anarchic era of Zemene Mesafint("Era of the Princes"), in which rival warlords fought for power and the Yejju Oromo "enderase"s ("regents") had effective control. The emperors were considered to be figureheads. Until a young man named Kassa Haile Giorgis also known as Emperor Tewodros brought end to "Zemene Mesafint" by defeating all his rivals and took the throne in 1855. The Tigrayans made only a brief return to the throne in the person of Yohannes IV in 1872, whose death in 1889 resulted in the power base shifting back to the dominant Amharic-speaking elite prior to Yejju Oromo and Tigrayan rule. His successor Menelik II an Emperor of Amhara origin seized power. League of Nations in 1935 reported that after the invasion of Menelik's forces into non Abyssinian-proper lands of Somalis, Harari, Southern Oromo, Sidama, Shanqellaetc., the inhabitants were enslaved and heavily taxed by the gebbar-feudal system leading to depopulation.


title: Ethiopia

text: Some scholars consider the Amhara to have been Ethiopia's ruling elite for centuries, represented by the Solomonic line of Emperors ending in Haile Selassie I. Marcos Lemma and other scholars dispute the accuracy of such a statement, arguing that other ethnic groups have always been active in the country's politics. This confusion may largely stem from the mislabeling of all Amharic-speakers as "Amhara" even though they were from a different ethnic group, and the fact that many people from other ethnic groups have adopted Amharic names. Another is the claim that most Ethiopians can trace their ancestry to multiple ethnic groups, including the last self-proclaimed emperor Haile Selassie I and his Empress Itege Menen Asfaw of Ambassel of having both Amhara and Oromo linage.


title: Ethiopia

text: Oromo migrations, occurred with the movement of a large pastoral population from the southeastern provinces of the Empire. A contemporary account was recorded by the monk Abba Bahrey, from the Gamo region. Subsequently, the empire organization changed progressively, with faraway provinces taking more independence. A remote province such as Bale is last recorded paying tribute to the imperial throne during Yaqob reign (1590-1607).


title: Ethiopia

text: By 1607, Oromos were also major players in the imperial politics, when Susenyos I, raised by a clan through "gudifacha"(or adoption), took power. He was helped by fellow Luba age-group generals Mecha, Yilma and Densa, who were rewarded by "Rist" feudal lands, in the present-day Gojjam districts of the same name.


title: Ethiopia

text: The reign of Iyasu I the Great (1682-1706) was a major period of consolidation. It also saw the dispatching of embassies to Louis XIV's France and to Dutch India. During the reign of Iyasu II (1730-1755), the Empire was strong enough to undertake a war on the Sennar Sultanate, where the emperor leading its army to Sennar itself, was afterwards forced to retreat upon defeat along the Setit river. Iyasu II also conferred the dignity of Kantibai of the Habab (northern Eritrea) after homage by a new dynasty.


title: Ethiopia

text: The "Wallo" and "Yejju" clans of the Oromo people rise to power culminated in 1755, when Emperor Iyoas I ascended to the imperial throne in Gondar. They would be one of the major factions contending for imperial power during the ensuing Zemene Mesafint, starting from 1769, when Mikael Sehul, Ras of Tigray killed Iyoas I and replaced him with Yohannes II.


title: Ethiopia

text: The establishment of modern Ethiopia was led by the Shawan people (which included both Amharas and Oromos), particularly Amhara emperors Tewodros II of Gondar, who governed from 1855 to 1868, Yohannis IV, who was from Tigray governed from 1869 to 1889 and managed to expand his authority into Eritrea, and Menelik II, who governed from 1889 to 1913 and repelled the Italian invasion of 1896.


title: Ethiopia

text: From 1874 to 1876, the Empire, under Yohannes IV, won the Ethiopian-Egyptian War, decisively beating the invading forces at the Battle of Gundet, in Hamasien province (in modern-day Eritrea). In 1887 Menelik king of Shewa invaded the Emirate of Harar after his victory at the Battle of Chelenqo.


title: Ethiopia

text: Beginning in the 1890s, under the reign of the Emperor Menelik II, the empire's forces set off from the central province of Shoa to incorporate through conquest inhabited lands to the west, east and south of its realm. The territories that were annexed included those of the Western Oromo (non-Shawan Oromo), Sidama, Gurage, Wolayta, and Dizi. Among the imperial troops was Ras Gobena's Shewan Oromo militia. Many of the lands that they annexed had never been under the empire's rule, with the newly incorporated territories resulting in the modern borders of Ethiopia.


title: Ethiopia

text: Ethiopia, unlike the rest of Africa, had never been colonized. Ethiopia was accepted as the first independent African-governed state at the League of Nations in 1922. Ethiopia was occupied by Italy after the Second Italo-Abyssinian War, but it was liberated by the Allies during World War II.


title: Ethiopia

text: After the war, Ethiopia annexed Eritrea. However, ethnic tensions surged between the Amhara and the various ethnic groups of Eritrea, as well as Oromo, Somali, and Tigray peoples, in Ethiopia proper, each of whom had formed separatist movements dedicated to leaving Ethiopia. After the overthrow of the Ethiopian monarchy by the Derg military junta, the country became aligned with the Soviet Union and Cuba after the United States failed to support it in its military struggle with Somali separatists in the Ogaden region. After the end of military government in Ethiopia in 1993, Eritrea separated from Ethiopia.


title: Ethiopia

text: The Kingdom of Aksum, the first known kingdom of great power to rise in Ethiopia, rose during the first century AD. The Persian religious figure Mani listed Axum with Rome, Persia, and China as one of the four great powers of his time. It was in the early 4th century that a Syro-Greek castaway, Frumentius, was taken to the court and over time changed King Ezana to Christianity, making Christianity Ethiopia's religion. For this, he received the title "Abba Selama". At different times, including a time in the 6th century, Axum ruled most of modern-day Yemen just across the Red Sea.


title: Ethiopia

text: The line of rulers of the actual Axumite kings ended around 950 AD when they were overthrown by the Jewish Queen Gudit; then it was followed by the Zagwe dynasty for around 300 years. Around 1270 AD, the Solomonid dynasty came to control Ethiopia, claiming that they were related to the kings of Axum (though their claim was unscientific, they were even southern Ethiopia people, like from Shewa and such). They called themselves "Neguse Negest" ("King of Kings," or Emperor), basing their claims on their direct relation to king Solomon and the queen of Sheba.


title: Ethiopia

text: During the rule of Emperor Lebna Dengel, Ethiopia made its first good contact with a European country, Portugal in 1520. When the Empire was attacked by Somali General and Imam, Ahmad ibn Ibrihim al-Ghazi, Portugal responded to Lebna Dengel's request for help with 400 musketeers, helping his son Gelawdewos beat al-Ghazi and remake his rule. However, Jesuit missionaries over time offended the Orthodox faith of the local Ethiopians, and in the mid-17th century Emperor Fasilidos got rid of these missionaries. At the same time, the Oromo people began to question the Ethiopian Christian authorities in the Abyssinian territories, and wanted to keep their own religion.


title: Ethiopia

text: All of this led to Ethiopia's isolation during the 1700s. The Emperors became figureheads, controlled by warlords like Ras Mikael Sehul of Tigray. But Amharic is the national language of Ethiopia. Ethiopian isolationism ended following a British mission that made friendship between the two nations; however, it was not until the reign of Tewodros II that Ethiopia began to take part in world matters once again.


title: Ethiopia

text: In 1896 Italy was decisively defeated in the battle of Adwa by Emperor Menelik; an Amhara Emperor from the province of Shewa. This battle dispelled the notion that Europeans were superior and could not be defeated by a black army. It gave rise to the Pan African movement, and hope to other African countries who were conquered. This victory made Ethiopia the only African country to successfully repel a European power during the Scramble of Africa. In 1936 Italy again attacked, and succeeded in occupying Ethiopia until 1941. With British help the 5 year occupation ended and Emperor Haile Selassie regained the throne.


title: Ethiopia

text: Revolutionaries overthrew and killed the emperor in 1974. The resulting civil war lasted until 1991. Eritrea became independent and later fought the Eritrean–Ethiopian War.


title: Ethiopia

text: Ethiopians are the native inhabitants of Ethiopia, as well as the global diaspora of Ethiopia. Ethiopians constitute several component ethnic groups, many of which are closely related to ethnic groups in neighboring Eritrea and other parts of the Horn of Africa.


title: Ethiopia

text: Ethiopia's population is highly diverse with different languages and ethnic groups. Most of its people speak a Semitic or Cushitic language which are both part of the Afroasiatic language family, while others speak Nilo-Saharan languages. The Oromo, Amhara, Somali and Tigrayans make up more than three-quarters (75%) of the population, but there are more than 80 different ethnic groups within Ethiopia. Some of these have as few as 10,000 members.


title: Ethiopia

text: Ethiopian nationalism, also referred to as Ethiopianism, Ethiopianness (Amharic: ኢትዮጵያዊነት, Ityop̣p̣yawinnät), Pan-Ethiopian nationalism, or Ethiopian national identity, is a political principle of Civic Nationalism centered on the unification of Ethiopian identity asserting that Ethiopians are a nation and promotes the equality of all component ethnic groupsconstituting as one multi-ethnic and multicultural sovereign polity.


title: Ethiopia

text: The view espoused by Ethiopian nationalists is that Ethiopian civic nationalism (that it is multi-ethnic in nature and promotes multiculturalism among all component ethnic groups) is in contrast to and in opposition against ethno-nationalistsupremacism fueled by ethnic federalist policies introduced by the EPRDF in which Ethiopian nationalists claim that regional subdivisions of the state were segregatedaccording to ethnicity brought about by the partitioning and dissolution of traditionally multi-ethnic regions causing the internal displacement of people through internal population transfers.


title: Ethiopia

text: However, there has been opposition to multi-ethnic Ethiopian civic nationalismfrom ethnic nationalist and separatists groups as seen in the surge of ethnic tensions between various Ethiopian ethnic groups and political parties most notably among the most populous ethnic groups in the country such as the Amhara, Oromo, Somali, and Tigray peoples, most of whom who have separatist movements among their ranks, and conflict between Ethiopia and various ethnic groups that make up the Eritrean population with Eritrean Provincial Separatists vying for and later accomplishing the independence of Eritrea(who had already formed their own region specific Eritrean Nationalism and national identity of the Eritreans which has keen similarities to that of Ethiopian civic nationalism because of its multi-ethnic nature). In the aftermath of the ShewanNeftenya period that occurred, as a result of feudal lords from Shewa settling in the southern regions, other ethnic groups assimilated into the royal court culture by adopting the Amharic language, Orthodox Christianity, and other aristocratic cultural traits. The Amhara culture-influenced royal court culture dominated throughout the eras of military and monarchic rule. Both peasant Amhara culture and Ethiopian Empire royal court culture have heavily influenced each other; this Ethiopian royal court culture (that influenced and was influenced by Amhara culture) but is separate from traditional peasant Amhara culture, dominated throughout the eras of military and monarchic rule. The difference between the average Amhara people (generally those of the peasant class) and high status royal court class (which was multi-ethnic but adopted the Amharic language) are described by Siegfried Pausewang says that "the term Amhara relates in contemporary Ethiopia to two different and distinct social groups. The ethnic group of the Amhara, mostly a peasant population, is different from a mixed group of urban people coming from different ethnic background, who have adopted Amharic as a common language and identify themselves as Ethiopians".Due to language and certain cultural similarities, the multi-ethnic ruling class of the military and monarchic era has erroneously been described as an Amhara ruling class, in addition to the questionable existence of an ethnic group known as the Amhara people during the time periods in question, has erroneously made the terms interchangeable (even within this article). Aspects of Ethiopian nationalism have been described as a political principle centered at unification of Ethiopian identity. The ideology was promulgated throughout ancient history, from Ethiopian Empire and the Dergrule.


title: Ethiopia

text: For more than a century, Amhara ruling elite used this ideology to pursue an assimilation policy and consolidate power. The conflict started between Abyssinia, ruled by Amhara ethnic groups, and various subjugated ethnic groups such as Oromo, Sidama, and Tigray. In 1991 Eritrea achieved independence as the Derg collapsed and the TPLF assumed power and created an ethnic-federal state. The Amhara culture dominated throughout the eras of military and monarchic rule. Both the Haile Selassieand Derg governments relocated numerous Amharas into southern Ethiopia including the present-day Oromia Region, where they served in government administration, courts, church and even in schools, where Oromo texts were eliminated and replaced by Amharic. As a result of these steps, ethnic tensions surged against the Neftenya system where the Oromo, Somali, and Tigray peoples, each of whom had formed separatist movements such as the OLF, TPLF, ELF and ONLF struggled to leave the Ethiopian Empire, which led to the Ethiopian Civil War. Oromo ethnic nationalists and Ethiopian civic nationalists continue to have conflicting narratives over the status of Addis Ababa. Oromo ethnic nationalist claim that Addis Ababa should be ceded to Oromia Region and/or lead by Oromo people, while Ethiopian civic nationalists believe that it should stay as an independent city with leadership open to all people regardless of ethnicity. The Abyssinian elites perceived the Oromo identity and languages as hindrances to Ethiopian national identity expansion.


title: Ethiopia

text: It originated from throughout ancient history, the Aksumite Empire was the first kingdom for their unified civilization and social integration to adopt the name "Ethiopia" under Ezana's reign in 4th century. For more than a century, Amhara ruling elite used the ideology to pursue an assimilation policy and consolidate power. Moreover, the notion of Ethiopian integrity was reinforced by Battle of Adwa, an important event where Ethiopia defied European colonization by defeating Italy in 1896.


title: Ethiopia

text: The Second Italo-Ethiopian War and subsequent Italian occupation of Ethiopia appeared to be foreign aggression and civil war that leads to ethnic faction expressed by student movements. Following the abolition of monarchy and overthrow of Haile Selassie by communist military junta Derg in 1974, Ethiopia underwent several conflicts and civil wars that persists up to today, and the 1991 downfall of the Derg and the raise of the Ethiopian People's Revolutionary Democratic Front (EPRDF) and its ethnic nationalist policies promoted continuum violence and thwarted the Ethiopian unity.


title: Ethiopia

text: In 1991, the TPLF had gained almost complete control of the national government, leveraging its power to concentrate wealth and development into the Tigray Region. The hegemonic rule of the Tigray people in Ethiopia was in many ways a reaction to the predominance Amharas had in media and governance. The hegemonic rule of a few ethnic groups or in some cases, a single ethnic group has marginalized many groups within Ethiopia and has led to a cycle of violence and retribution. In the early 1990s, the TPLF believed that through an ethnic federalist state system, one in which regions were assigned and divided by the ethnic population, they could:reduc[e] the inter-ethnic conflict that has divided Ethiopian society for centuries; promot[e] equitable material conditions in all areas of the country; and improv[e] the efficiency and effectiveness of public sector performance at the field level. They argued they could use political and administrative devolution to promote these objectives without threatening other important objectives, such as economic growth and political stability.While these regions were not given "extensive sub-national control over technical policies, laws, regulations, and tax," their creation lent credibility to the different independence and ethnic nationalist movements around the country. For Ethiopian nationalists, this credibility has emboldened different groups, giving them more cohesion, whilst corroding national unity and notions of Pan-Ethiopianism. The increased autonomy of these groups contrasted with the increased repression by Tigray elites created a situation in which the ruling class was both empowering groups through greater ethnic cohesion, but transparently stifling their political will. As shown by the 2005 elections, the TPLF use of violent repression to subdue detractors of the ruling coalition only had the effect of radicalizing ethnic parties and increasing ethnic divisions. Many Ethiopian nationalists view the system of ethnic federalism as having made governing in Ethiopia a zero-sum game. To win power in Ethiopia is to deny any other ethnic group significant power. By expelling notions of Ethiopianism or multi-ethnic Ethiopian national identity from the national political dialogue, the TPLF has increased the ethnic breaks and created a system revolving around ethnic affiliation, devoid of political ideology. In 2015, after a master plan was unveiled to expand the boundaries of the Ethiopian capital Addis Ababa into Oromia in 2014, thousands of Oromo Youth Liberation Movement members took to the streets to demand increased political representation, an end to the TPLF-sponsored Master Plan, and avenues of dissent. Although the ruling party tried to blunt these protests through physical force, the protests only grew. Amharas "angered by an unfulfilled demand to retake control of some of their lands" launched protests consisting of mostly Oromos and Amharas (but also other Ethiopians) demanding proportional political representation and influence.After a 10-month state of emergency imposed by the TPLF, which saw the abdication of prime minister Hailemariam Desalegn and Abiy Amhed—was selected by the ruling EPDRF coalition as the next prime minister due to his mixed Oromo-Amhara ethnic ancestry with a preference for his Oromo identity. Since Abiy took power, he has taken up major reforms allowing back political dissidents, releasing some political prisoners, and liberalizing the economy. While his drive to reform and democratize the nation has garnered him support across the country, he still has not addressed the fundamental issues of the ethnic federalist system, which in the Pan-Ethiopians' opinion is the root cause for ethno-nationalist politics and tensions. Ethiopian nationalists believe that ethnic federalism must be ended to shift Ethiopian politics from ethnic patronage to ideology, it must be ended to induce national cohesion and blunt sectarian loyalty, and through the blunting of ethnic cohesion induce an era of unity and prosperity.


title: Ethiopia

text: Abiy and the Prosperity Party have been seen as supporters of Ethiopian civic nationalism due to the merger of the Oromo Democratic Party with the ethnicity-based Amhara Democratic Party, Argoba People's Democratic Organization, Benishangul-Gumuz People's Democratic Unity Front, Ethiopian Somali People's Democratic Party, Gambela People's Democratic Movement, Afar National Democratic Party, Hareri National League, and the Southern Ethiopian People's Democratic Movementpolitical parties into the new multi-ethnic Prosperity Party, thus moving these predecessor parties away from their ethnic nationalist and pro-ethnic federalism past into a party that promotes Ethiopian national identity, and non-ethnicity based federalism. All of these goals are seen by opponents as steps towards taking political powers based on group rights away from the various ethnic groups. Proponents of the merger see it as a way to move Ethiopian politics and governmental administration away from ethnicity-based identity politics, supporting the individual rights of each person. This outlook more intensely mitigates rising ethnic nationalism, fosters national unity and solidarity, and creates inclusive democratic processinvolving political parties of several ethnic groups and regions that were once deemed too inferior by the Tigray People's Liberation Front-led Ethiopian People's Revolutionary Democratic Front regime to be included in the one-party dominated coalition government or be full partakers in the collation's revolutionary democracy because of their largely pastoralist way of life.


title: Ethiopia

text: Before 1996, Ethiopia was divided into 13 provinces. Ethiopia now has ethnically based regional states, zones, districts, and neighborhoods.


title: Ethiopia

text: There are nine regions, sixty-eight zones and two chartered cities. Ethiopia is further divided into 550 "woredas" and several "special woredas".


title: Ugli fruit

text: An ugli is a type of citrus fruit. It is related to the lemon family. It started to grow quickly all across Jamaica over 80 years ago and was quickly discovered by the natives there. It became popularly known, but it did not have a name. The natives on Jamaica named it the ugli fruit because of its ugly appearance. It was shipped to the United States and South America on cargo ships and after it arrived in the Americas, its popularity only grew. The original fruit is believed to have been a hybrid formed from the Seville orange, the grapefruit, and the tangerine families.


title: Gas

text: A gas is one of the four states of matter. In a gas, the molecules move freely and are not attached to each other. This makes it different from a liquid where the molecules are loosely attached to or touching each other. It is also different from a solid where the molecular bonds are strong and hold the molecules together in one shape.


title: Gas

text: A gas does not have only one volume like a liquid or solid does. Instead, gas can expand until it fills whatever container it is in.


title: Gas

text: In a pure gas, each molecule may be made of an individual atom. It may be elemental, where each molecule is made of more than one of the same atom bound together. It may be compounds where molecules are made of many types of atoms together. An example of a monoatomic gas is neon, an example of an elemental gas is hydrogen and an example of a compound gas is carbon dioxide.


title: Gas

text: A gas mixture contains a mix of any of the above types, for example air which is 87% nitrogen, 0.2% oxygen and 13.7% argon and carbon dioxide.<0.0009></33.3456333>


title: Gas

text: Poison gases were used as chemical weapons in War I but were later banned. gas is a natural mixture of methane and other gases.


title: Gas

text: All gases can flow, like liquids. This means the molecules move about independently of each other. Most gases are colourless, like hydrogen. Gas particles will spread about, or diffuse, in order to fill all the space in any container such as a bottle or a room. Compared to liquids and solids, gases have a very low density and viscosity. We cannot directly see most gases since they aren't coloured. However it is possible to measure their density, volume, temperature and pressure.


title: Gas

text: Pressure is the measure of how much pushing force something is putting on another object. In a gas, this is usually the gas pushing on the container of the object or, if the gas is heavy, something inside the gas. Pressure is measured in pascals. Because of Newton's third law, we can change the pressure of a gas by putting force on the object containing it. For example, squeezing a bottle with air inside pressurises (gives more pressure) to the air inside.


title: Gas

text: When talking about gas, pressure is often related to the container. A lot of gas in a small container would have very high pressure. A small amount of a gas in a big container would have low pressure.


title: Gas

text: Gas can create pressure itself when there is a lot of it. The weight of the gas creates pressure on anything underneath it, including other gas. On a planet, this is called atmospheric pressure.


title: Gas

text: The temperature of a gas is how hot or cold it is. In physics it is usually measured in kelvins although degrees Celsius are used more elsewhere. In a gas, the average velocity (how fast they move) of the molecules is related to the temperature. The faster the gas molecules are moving, the more they collide, or smash into each other. These collisions release energy, which in a gas comes in the form of heat. Conversely if the temperature around the gas becomes hotter then the gas particles will convert the thermal energy to kinetic energy, making them move faster and making the gas hotter.


title: Gas

text: A gas can go through two different state changes. If the temperature is low enough the gas can condense and turn into a liquid. Sometimes, if the temperature is low enough it can go through deposition, where it changes straight to a solid. Normally a gas must first condense to a liquid, and then freeze to become a solid, but if the temperature is very low it can skip the liquid stage and instantly become solid. Frost on the ground in winter is caused by this. Water vapour (a gas) goes into the air which is very cold, and instantly becomes ice due to deposition.


title: Australoid (race)

text: Australoid race was a word for the aboriginal people of Australia, Melanesia, and parts of Southeast Asia. In former times, many people divided human beings into four races. These races were called "Australoid", "Mongoloid", "Caucasoid", and "Negroid". Today, scientists agree that there is only one human race. Modern genetic research has shown that the idea of four races was wrong.


title: Dictatorship

text: A dictatorship is a form of government, where one person effectively has all the power to run a country. In very few cases, a small group of people holds this power. This person is called a dictator. A dictatorship that is ruled by soldiers is called a military dictatorship or junta. An absolute monarchy (the system where there are Kings and Queens who have full power over their country) can be considered to be a dictatorship, but the people are usually not called dictators.


title: Dictatorship

text: Roman dictators were temporary rulers appointed to protect the state during a war or other emergency. Many countries have laws that allow a similarly time-limited dictatorship, to fight against such problems. Karl Marx has the idea of the Dictatorship of the proletariat. When they became independent in the 1960s and 1970s, many African states changed to be dictatorships, run by one person. Karl Popper distinguished between two different forms of government, "Those where it is possible to change the government without bloodshed, in a popular vote, and those where it isn't." He said that this was the key difference, and not how the forms of government are named.


title: Dictatorship

text: Dictators often come to power in times of difficulty, such as massive unemployment, inflation, and unrest among the population. Dictators are normally backed by powerful groups, such as landowners, private company owners, bank owners and in some cases institutions like the Roman Catholic Church to put in place law and order by force. This force may be directed at the poorer parts of society, such as unemployed workers, ethnic minorities, working class areas andshanty towns. Examples of this are the dictatorships in Latin America and the prosecution of the Jewish community in 1940s Germany.


title: Dictatorship

text: Dictators normally need to do a number of things to put in place their dictatorships: they need to get rid of their opponents (which may be political or religious) - some are imprisoned, exiled (sent outside their country) or killed. Dictators will then need to prohibit (or not allow) political parties that oppose their rule. They will confiscate the political parties' property or offices and such things. Dictators may suppress or persecute some religious groups or institutions. Dictators will also need to undo or close down democratic institutions such as parliament and in some cases the congress.


title: Dictatorship

text: Some social organizations, such as civil rights groups, human rights organisations, legal aid centers, students' unions, teachers' federations, trade or workers unions are also undone and those who persist with such activities may be killed. Dictators often rewrite an existing constitution or put in place a completely new one. This makes their power constitutional (which then cannot be disputed). Dictators then maintain their rule with state terrorism, which normally involves a secret police, death squads, random or night curfew, indefinite arrest without trial and a network of torture centers and concentration camps. Some dictatorships create a fictional (or non existent) internal (inside their country) enemy which they claim to be at war with to justify (give reason for) their use of much military violence against their people.


title: E (mathematical constant)

text: The number has great importance in mathematics, as do 0, 1, , and . All five of these numbers are important and occur again and again in mathematics. The five constants appear in one formulation of Euler's identity. Like the constant , is also irrational (it cannot be represented as a ratio of integers) and transcendental (it is not a root of any non-zero polynomial with rational coefficients).


title: E (mathematical constant)

text: The number is very important for exponential functions. For example, the exponential function applied to the number one, has a value of .


title: E (mathematical constant)

text: There are many different ways to define . Jacob Bernoulli, who discovered , was trying to solve the problem:


title: E (mathematical constant)

text: In other words, there is a number that the expression formula_2 approaches as "n" becomes larger. This number is .


title: Saare Jahan se Achcha

text: Saare Jahan se Achcha is a poem. It was re-written in 1931. It became a symbol of resistance to the English rule of British-occupied India. The poem exists in different versions. Saare Jahan Se Achchha () is one of the enduring patriotic poems of the Urdu language. Written originally for children in the ghazal style of Urdu poetry by poet Muhammad Iqbal, the poem was published in the weekly journal Ittehad on 14 August 1931. Recited by Iqbal the following year at Government College, Lahore, now in Pakistan, it quickly became an anthem of opposition to the British rule in India.


title: Charles Darwin

text: Charles Robert Darwin (12 February 1809 – 19 April 1882) was an English naturalist. He was born in Shrewsbury, Shropshire. He is famous for his work on the theory of evolution.


title: Charles Darwin

text: His book "On the Origin of Species" was published in 1859. In this book, he put forward much evidence that evolution had occurred. He also proposed natural selection as the way evolution had taken place.


title: Charles Darwin

text: Darwin did not know about genetics: he never read the work of Gregor Mendel. Nevertheless, Darwin's explanation of evolution was fundamentally correct. In contrast to Lamarck, Darwin's idea was that the giraffe's neck became longer because "those with longer necks survived better". These survivors passed their genes on, and in time the whole species got longer necks.


title: Charles Darwin

text: Darwin spent almost five years on board a Royal Navy exploring ship, the HMS "Beagle". He was the guest naturalist, which meant that he was responsible for making collections and notes about the animals, plants, and the geology of the countries they visited. The ship's crew made charts of all the coastal areas, which could be used by the navy wherever it went in the world. At the time, Britain had by far the largest navy in the world, and an empire which was global.


title: Charles Darwin

text: Darwin collected everywhere the ship landed. He found huge fossils of recently extinct mammals, experienced an earthquake in Chile, and noticed the land had been raised. He knew of raised beaches elsewhere, high in the Andes, with fossil seashells and trees which had once grown on a sandy beach. Obviously the earth was constantly changing, with land rising in some places, and sinking in others. He collected birds and insects, and sent shipments back to Cambridge for experts to identify.


title: Charles Darwin

text: Darwin was the first dedicated naturalist to visit the Galapagos Islands, off the west coast of Ecuador. He noticed that some of the birds were like mockingbirds on the mainland, but different enough to be placed in separate species. He began to wonder how so many new species came to be on these islands.


title: Charles Darwin

text: When Darwin got back to England, he edited a series of scientific reviews of the voyage, and wrote a personal journal which we know as "The Voyage of the Beagle". It is one of the great natural history travel diaries.


title: Charles Darwin

text: In 1843 Darwin, who already had two children with his wife Emma, bought Down House in the village of Downe, Kent. He lived there for the rest of his life, and today the house and contents are open to the public.


title: Charles Darwin

text: While on the H.M.S. "Beagle", and later back home in London, Darwin had come across the ideas of the Rev. T.R. Malthus. Malthus had realised that, although humans could double their population every 25 years, it did not happen in practice. He thought the reason was that a struggle for existence (or resources) limited their numbers. If numbers increased, then famine, wars and diseases caused more deaths. Darwin, who knew that all living things could, in principle, increase their numbers, began to think about why some survived, while others did not. His answer took years to develop.


title: Charles Darwin

text: The theory of evolution says that all living things on Earth, including plants, animals and microbes, come from a common ancestor by slowly changing throughout the generations. Darwin suggested that the way living things changed over time is through "natural selection". This is the better survival and reproduction of those that best fit their environment. Fitting into the place where you live is called adapting. Those who fit best into the place where they live, the best adapted, have the best chance to survive and breed. Those who are less well-adapted tend not to survive. If they do not survive well enough to raise young, this means they do not pass on their genes. In this way, the species gradually changes.