Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.
--------
Question: Problem: what is the compound interest paid on a sum of rs. 3000 for the period of 2 years at 10 % per annum.
Options: a. 630, b. 620, c. 610, d. 600, e. none of these

Answer: a


Question: Problem: a train traveling at 72 kmph crosses a platform in 33 seconds and a man standing on the platform in 18 seconds. what is the length of the platform in meters ?
Options: a. 240 meters, b. 360 meters, c. 420 meters, d. 300 meters, e. can not be determined

Answer: d


Question: Problem: an error 2 % in excess is made while measuring the sideofa square. the % of error in the calculated area of the square is ?
Options: a. 4 %, b. 4.04 %, c. 4.15 %, d. 5 %, e. 5.24 %

Answer:
b