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: a tank contains 7,500 gallons of a solution that is 6 percent sodium chloride by volume . if 2,000 gallons of water evaporate from the tank , the remaining solution will be approximately what percent sodium chloride ? 
Options: a ) 5.18 % , b ) 6.18 % , c ) 7.18 % , d ) 8.18 % , e ) . 7 %
[EX A]: d

[EX Q]: Problem: if 40 % of a number is greater than 80 % of 5 by 2 , what is the number ? 
Options: a ) 3 , b ) 15 , c ) 20 , d ) 2 , e ) 5
[EX A]: b

[EX Q]: Problem: after decreasing 24 % in the price of an article costs rs . 760 . find the actual cost of an article ? 
Options: a ) 1218 , b ) 2777 , c ) 1000 , d ) 2688 , e ) 1991
[EX A]:
c