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.

[EX Q]: Problem: car x began traveling at an average speed of 35 miles per hour. after 72 minutes, car y began traveling at an average speed of 49 miles per hour. when both cars had traveled the same distance, both cars stopped. how many miles did car x travel from the time car y began traveling until both cars stopped ?
Options: a. 105, b. 120, c. 140, d. 147, e. 168
[EX A]: a

[EX Q]: Problem: the ` ` racing magic ' ' takes 120 seconds to circle the racing track once. the ` ` charging bull ' ' makes 40 rounds of the track in an hour. if they left the starting point together, how many minutes will it take for them to meet at the starting point for the second time ?
Options: a. 3, b. 6, c. 9, d. 12, e. 15
[EX A]: d

[EX Q]: Problem: a shopkeeper has 280 kg of apples. he sells 40 % of these at 30 % profit and remaining 60 % at 30 % profit. find his % profit on total.
Options: a. 24 %, b. 25 %, c. 26 %, d. 28 %, e. 30 %
[EX A]:
e