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: x does a work in 20 days. y does the same work in 40 days. in how many days they together will do the same work ?
Options: a. 10, b. 12, c. 20, d. 30, e. 13.33
[A]: e


[Q]: Problem: the circumference of the front wheel of a cart is 30 ft long and that of the back wheel is 32 ft long. what is the distance traveled by the cart, when the front wheel has done five more revolutions than the rear wheel ?
Options: a. 20 ft, b. 25 ft, c. 750 ft, d. 900 ft, e. 2400 ft
[A]: e


[Q]: Problem: 15.06 * 0.00001 = ?
Options: a. 15060000, b. 0.0001506, c. 0.01506, d. 0.1506, e. none of these
[A]:
b