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: at a certain university, 65 % of the professors are women, and 70 % of the professors are tenured. if 90 % of the professors are women, tenured, or both, then what percent of the men are tenured ?
Options: a. 25, b. 37.5, c. 50, d. 62.5, e. 75

A: d
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Q: Problem: in a group of cows and chickens, the number of legs was 12 more than twice the number of heads. the number of cows was :
Options: a. 6, b. 7, c. 10, d. 12, e. 14

A: a
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Q: Problem: in the number 11,0 ab, a and b represent the tens and units digits, respectively. if 11,0 ab is divisible by 65, what is the greatest possible value of b × a ?
Options: a. 0, b. 5, c. 10, d. 15, e. 25

A:
c
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