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: how many liters of water must be evaporated from 50 liters of a 2 - percent sugar solution to get a 10 - percent solution ? 
Options: a ) 25 , b ) 30 , c ) 35 , d ) 40 , e ) 45
[A]: d


[Q]: Problem: alex takes a loan of $ 5,000 to buy a used truck at the rate of 2 % simple interest . calculate the annual interest to be paid for the loan amount . 
Options: a ) 100 , b ) 150 , c ) 720 , d ) 200 , e ) 750
[A]: a


[Q]: Problem: if the cost price is 90 % of the selling price , then what is the profit percent ? 
Options: a ) 5 % , b ) 11 % , c ) 13 % , d ) 21 % , e ) 19 %
[A]:
b