The task is to generate the correct answer for a given math problem.

Q: Problem: a swimmer can swim in still water at 4 km / h . if the speed of the water current is 2 km / h , how many hours will the swimmer take to swim against the current for 5 km ?

A: 2.5
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Q: Problem: the sum of all the digits of the integers from 18 to 21 inclusive is 24 ( 1 + 8 + 1 + 9 + 2 + 0 + 2 + 1 = 24 ) . what is the sum t of all the digits of the integers from 0 to 99 inclusive ?

A: 900
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Q: Problem: if n is a positive integer and n ^ 2 is divisible by 18 , then what is the largest positive integer that must divide n ?

A:
6
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