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 speed of a boat in still water is 15 km / hr and the rate of current is 3 km / hr. the distance travelled downstream in 24 minutes is
Options: a. 17.2 km, b. 7.2 km, c. 7.6 km, d. 17.6 km, e. 27.2 km

A: b
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Q: Problem: find the value o f 72519 x 9999 = m ?
Options: a. 434539873, b. 355797990, c. 435453490, d. m = 725117481, e. 873430134

A: d
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Q: Problem: how many multiples of 10 are there between 10 and 290 ?
Options: a. 8, b. 18, c. 27, d. 51, e. 60

A:
c
****