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

Q: Problem: the s . i . on a certain sum of money for 2 years at 8 % per annum is half the c . i . on rs . 4000 for 2 years at 10 % per annum . the sum placed on s . i . is ?

A: 262
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Q: Problem: the curved surface of a sphere is 64 π cm 2 . find its radius ?

A: 4', 'd ) 9', 'e ) 7'
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Q: Problem: a man can swim in still water at 12 km / h , but takes twice as long to swim upstream than downstream . the speed of the stream is ?

A:

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