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: two trains travel in opposite directions at 36 kmph and 45 kmph and a man sitting in slower train passes the faster train in 8 seconds. the length of the faster train is
Options: a. 80 m, b. 100 m, c. 120 m, d. 180 m, e. 160 m
[A]: b


[Q]: Problem: john and david can finish a job together in 2 hours. if john can do the job by himself in 3 hours, what percent of the job does david do ?
Options: a. 36.33 %, b. 33.33 %, c. 39.33 %, d. 40.33 %, e. 33 %
[A]: b


[Q]: Problem: 100 people are attending a newspaper conference. 35 of them are writers and more than 38 are editors. of the people at the conference, x are both writers and editors and 2 x are neither. what is the largest possible number of people who are both writers and editors ?
Options: a. 21, b. 26, c. 28, d. 30, e. 32
[A]:
b