In this task, you need to answer the given multiple-choice question on the gain. Gain is the value by which to multiply the input. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: an error 2 % in excess is made while measuring the side of a square . the percentage of error in the calculated area of the square is : 
Options: a ) 1.04 , b ) 2.04 , c ) 3.04 , d ) 4.04 , e ) none of these

A: d
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Q: Problem: the difference between compound interest and simple interest on a certain amount of money at 5 % per annum for 2 years is 17 . find the sum : 
Options: a ) 4500 , b ) 7500 , c ) 5000 , d ) 6800 , e ) none of these

A: d
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Q: Problem: a vendor bought toffees at 6 for a rupee . how many for a rupee must he sell to gain 25 % ? 
Options: a ) 2 , b ) 9 , c ) 6 , d ) 3 , e ) 5

A:
b
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