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.
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Question: 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

Answer: d


Question: Problem: a / ( b / c. in the expression above, a, b, and c are different numbers and each is one of the numbers 2, 3, or 6. what is the largest possible value of the expression ?
Options: a. 2 / 18, b. 6 / 3, c. 30 / 2, d. 18 / 2, e. 6 / 18

Answer: d


Question: Problem: the average monthly salary of 8 workers and one supervisor in a factory was 430. @ sswhen @ ssthe @ sssupervisor @ cc @ sswhose @ sssalary @ sswas @ ss 430. @ sswhen @ ssthe @ sssupervisor @ cc @ sswhose @ sssalary @ sswas @ ss 430. whenthesupervisor, whosesalarywas 430. when the supervisor, whose salary was 870 per month, retired, a new person was appointed and then the average salary of 9 people was $ $ 440 per month. the salary of the new supervisor is :
Options: a. 233, b. 960, c. 287, d. 771, e. 191

Answer:
b