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: a no. when divided by 281 gives a remainder 160, what remainder will be obtainedby dividingthe same no. 21 ?
Options: a. 21, b. 22, c. 23, d. 24, e. 25

A: a
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Q: Problem: if julie rows 32 km upstream and 72 km down steam taking 4 hours each, then the speed of the stream
Options: a. 1.5 kmph, b. 0.5 kmph, c. 0.4 kmph, d. 1.6 kmph, e. 2.5 kmph

A: b
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Q: Problem: 5 drainage pipes, each draining water from a pool at the same constant rate, together can drain a certain pool in 12 days. how many additional pipes q, each draining water at the same constant rate, will be needed to drain the pool in 4 days ?
Options: a. 6, b. 9, c. 10, d. 12, e. 15

A:
c
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