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: in 10 years, a will be twice as old as b was 10 years ago. if a is now 5 years older than b the present age of b is
Options: a. 37, b. 38, c. 39, d. 35, e. 41

A: d
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Q: Problem: the average of runs of a cricket player of 20 innings was 32. how many runs must he make in his next innings so as to increase his average of runs by 8 ?
Options: a. 96, b. 200, c. 128, d. 116, e. 122

A: b
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Q: Problem: if an object travels at 9 feet per second, how many feet does it travel in one hour ?
Options: a. 32400, b. 30000, c. 32000, d. 1800, e. 22000

A:
a
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