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.

[Q]: 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
[A]: a


[Q]: Problem: find the smallest number that should be multiplied with 54000 to make it a perfect cube.
Options: ['a. 4', 'b. 5', 'c. 6', 'd. 3', 'e. 7']
[A]: a


[Q]: Problem: a bag contains 6 black and 4 white balls. one ball is drawn at random. what is the probability that the ball drawn is white ?
Options: a. 3 / 4, b. 2 / 5, c. 1 / 7, d. 1 / 8, e. 4 / 3
[A]:
b