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: of 600 surveyed students , 20 % of those who read book a also read book b and 25 % of those who read book b also read book a . if each student read at least one of the books , what is the difference between the number of students who read only book a and the number of students who read only book b ? 
Options: a ) 20 , b ) 25 , c ) 30 , d ) 35 , e ) 75
[A]: e


[Q]: Problem: a bowl of fruit contains 10 apples and 23 oranges . how many oranges must be removed so that 50 % of the pieces of fruit in the bowl will be apples ? 
Options: a ) 3 , b ) 13 , c ) 14 , d ) 17 , e ) 20
[A]: b


[Q]: Problem: if each side of a square is increased by 25 % , find the percentage change in its area ? 
Options: a ) 56.29 % , b ) 56.25 % , c ) 56.95 % , d ) 53.25 % , e ) 36.25 %
[A]:
b