Provide your best answer for the following math problem. Give ONLY the answer, no other words or explanation.
For example:

Answer: <most likely answer, as short as possible; not a complete sentence, just the answer!>.

The problem is: find the compound interest on rs . 10,000 in 2 years at 4 % per annum , the interest being compounded half - yearly .
rs 824.32
2101.60.