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: if the cost price of 55 articles is equal to the selling price of 50 articles , then what is the percent profit ? 
Options: a ) 5 % , b ) 10 % , c ) 15 % , d ) 20 % , e ) 25 %
[A]: b


[Q]: Problem: the present population of a town is 280 . population increase rate is 10 % p . a . find the population of town after 1 years ? 
Options: a ) 100 , b ) 120 , c ) 200 , d ) 220 , e ) 308
[A]: e


[Q]: Problem: rs . 900 becomes rs . 956 in 3 years at a certain rate of simple interest . if the rate of interest is increased by 4 % , what amount will rs . 900 become in 3 years ? 
Options: a ) rs . 1020.80 , b ) rs . 1025 , c ) rs . 1064 , d ) data inadequate , e ) none of these
[A]:
c