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: what is the perimeter of a square field whose diagonal is 8 â ˆ š 2 ?
Options: a. 64 m, b. 32 m, c. 30 m, d. 16 m, e. 18 m

A: b
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Q: Problem: a man bought an article and sold it at a gain of 5 %. if he had bought it at 5 % less and sold it for re 5 less, he would have made a profit of 10 %. the c. p. of the article was
Options: a. 960, b. 980, c. 900, d. 970, e. 1000

A: e
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Q: Problem: at company x, senior sales representatives visit the home office once every 12 days, and junior sales representatives visit the home office once every 8 days. the number of visits that a junior sales representative makes in a 2 - year period is approximately what percent greater than the number of visits that a senior representative makes in the same period ?
Options: a. 10 %, b. 25 %, c. 33 %, d. 50 %, e. 67 %

A:
d
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