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: the arithmetic mean and standard deviation of a certain normal distribution are 14.5 and 1.7, respectively. what value is exactly 2 standard deviations less than the mean ?
Options: a. 10.5, b. 11, c. 11.1, d. 12, e. 12.5

A: c
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Q: Problem: ravi purchased a refrigerator and a mobile phone for rs. 15000 and rs. 8000 respectively. he sold the refrigerator at a loss of 5 percent and the mobile phone at a profit of 10 percent. overall he make a.
Options: a. 50, b. 288, c. 27, d. 200, e. 881

A: a
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Q: Problem: brenda and sally run in opposite direction on a circular track, starting at diametrically opposite points. they first meet after brenda has run 50 meters. they next meet after sally has run 150 meters past their first meeting point. each girl runs at a constant speed. what is the length of the track in meters ?
Options: a. 250, b. 300, c. 350, d. 400, e. 500

A:
a
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