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: 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: a fruit juice company earns $ 150 per 100 gallons of apple juice sold, $ 170 per 100 gallons of guava juice sold, $ 130 per 100 gallons of grape juice sold, $ 100 per 100 gallons of orange juice. if the company manages to sell 230 gallons of apple, 210 gallons of guava, 310 gallons of grape, 270 gallons of orange on a particular day. what is the average earning of the company per 100 gallon of the juice sold ?
Options: a. 134.8, b. 141.2, c. 147.2, d. 152.3, e. 160.1

A:
a
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