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.

[EX Q]: Problem: list r contains 5 numbers that have an average value of 60. if the median of the numbers in the list is equal to the mean and the largest number is equal to 20 more than two times the smallest number, what is the smallest possible value in the list ?
Options: a. 25, b. 28, c. 31, d. 34, e. 37
[EX A]: b

[EX Q]: Problem: if the area of a circle decreases by 66 %, then the radius of a circle decreases by
Options: a. 20 %, b. 18 %, c. 36 %, d. 64 %, e. none of these
[EX A]: e

[EX Q]: Problem: the area of a triangle is with base 10 m and height 5 m ?
Options: a. 11, b. 25, c. 787, d. 122, e. 12
[EX A]:
b