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.

Input: Consider Input: Problem: a man spends 2 / 5 of his salary on house rent, 3 / 10 of his salary on food and 1 / 8 of his salary on convenience he has rs. 1400 left with him, find his expenditure on food and conveyance.
Options: a. 1000, b. 3000, c. 4000, d. 2000, e. 5000

Output: a


Input: Consider Input: Problem: mary works in a restaurant a maximum of 70 hours. for the first 20 hours, she is paid $ 8 per hour. for each overtime hour, she is paid at a rate which is 25 % higher than her regular rate. how much mary can earn in a week ?
Options: a. 600, b. 620, c. 660, d. 320, e. 400

Output: c


Input: Consider Input: Problem: the distance between two cities a and b is 330 km. a train starts from a at 8 a. m. and travel towards b at 60 km / hr. another train starts from b at 9 a. m and travels towards a at 75 km / hr. at what time do they meet ?
Options: a. 10 a. m, b. 10.30 a. m, c. 11 a. m, d. 11.30 a. m, e. none of these


Output: c