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.

Problem: the area of a triangle is with base 18 m and height 6 m ?
Options: a. 88 m 2, b. 10 m 2, c. 66 m 2, d. 54 m 2, e. 31 m 2
d

Problem: a shopkeeper buys mangoes at the rate of 5 a rupee and sells them at 2 a rupee. find his net profit or loss percent ?
Options: a. 34 %, b. 30 %, c. 50 %, d. 150 %, e. 33 %
d

Problem: the sector of a circle has radius of 28 cm and central angle 135 o. find its perimeter ?
Options: a. 122 cm, b. 92.2 cm, c. 28.9 cm, d. 29.2 cm, e. 98.2 cm

a