observe clouds forming measure the air temperature blow up a beach ball or balloon weigh a glass before and after it is filled with water
I gave my students this multiple choice question: Air has no color and cannot be seen, yet it takes up space. What could be done to show that air takes up space?

Only one answer is correct among these 4 choices:
- observe clouds forming
- measure the air temperature
- blow up a beach ball or balloon
- weigh a glass before and after it is filled with water

Could you tell me which one is correct?

blow up a beach ball or balloon