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'.

[EX Q]: Problem: at what rate percent per annum will the simple interest on a sum of money be 1 / 5 of the amount in 10 years ? 
Options: a ) 2 % , b ) 7 % , c ) 9 % , d ) 3 % , e ) 1 %
[EX A]: a

[EX Q]: Problem: a reduction of 20 % in the price of oil enables a house wife to obtain 10 kgs more for rs . 1500 , what is the reduced price for kg ? 
Options: a ) rs . 20 , b ) rs . 25 , c ) rs . 30 , d ) rs . 35 , e ) rs . 40
[EX A]: c

[EX Q]: Problem: a 6 % stock yields 8 % . the market value of the stock is ? 
Options: a ) rs . 11 , b ) rs . 75 , c ) rs . 17 , d ) rs . 16 , e ) rs . 22
[EX A]:
b