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: simple interest on a certain sum at a certain annual rate of interest is 1 / 9 of the sum . if the numbers representing rate percent and time in years be equal , then the rate of interest is : 
Options: a ) 5 , b ) 8 , c ) 3 1 / 3 , d ) 2 2 / 3 , e ) none of these
[A]: c


[Q]: Problem: sheela deposits rs . 5000 in bank savings account . if this is 20 % of her monthly income . what is her monthly income in ? 
Options: a ) 22000 , b ) 20000 , c ) 25000 , d ) 22235 , e ) none of these
[A]: c


[Q]: Problem: a merchant marks goods up by 75 % and then offers a discount on the marked price . the profit that the merchant makes after offering the discount is 57.5 % . what % discount did the merchant offer ? 
Options: a ) 10 % , b ) 15 % , c ) 20 % , d ) 25 % , e ) 30 %
[A]:
a