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 rate percent when the simple interest on rs. 720 amount to rs. 180 in 4 years ?
Options: a. 6.25, b. 7.25, c. 8.25, d. 9.25, e. 10.25
[A]: a


[Q]: Problem: if x ^ 2 – 4 x = 5, then one possible value of x – 2 =
Options: a. - 9, b. - 5, c. - 3, d. - 1, e. 5
[A]: c


[Q]: Problem: the diagonals of a rhombus are 10 cm and 12 cm. find its area ?
Options: a. 158, b. 60, c. 150, d. 123, e. 117
[A]:
b