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: in what time will a train 50 m long cross an electric pole, it its speed be 360 km / hr ?
Options: a. 0.25, b. 0.5, c. 1.5, d. 2.5, e. 3.5
[A]: b


[Q]: Problem: the average age of 17 persons in a office is 15 years. out of these, the average age of 5 of them is 14 years and that of the other 9 persons is 16 years. the age of the 15 th person is ?
Options: a. 39, b. 41, c. 45, d. 42, e. 50
[A]: b


[Q]: Problem: students at a school were on average 180 cm tall. the average female height was 170 cm, and the average male height was 184 cms. what was the ratio a of men to women ?
Options: a. 5: 2, b. 5: 1, c. 4: 3, d. 4: 1, e. 3: 1
[A]:
a