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: what will be the difference between simple and compound interest @ 20 % per annum on a sum of $ 500 after 2 years ? 
Options: a ) $ 10 , b ) $ 20 , c ) $ 25 , d ) $ 30 , e ) $ 40

A: b
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Q: Problem: what profit percent is made by selling an article at a certain price , if by selling at 2 / 3 rd of that price , there would be a loss of 14 % ? 
Options: a ) 20 % , b ) 29 % , c ) 13 1 / 30 % , d ) 12 % , e ) 13 %

A: b
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Q: Problem: two numbers are respectively 20 % and 25 % more than a third number . the percentage that is first of the second is ? 
Options: a ) 80 % , b ) 85 % , c ) 96 % , d ) 125 % , e ) 150 %

A:
c
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