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: what is the value of a s 81 % ?
Options: a ) 25 % , b ) 36 % , c ) 42 % , d ) 60 % , e ) 90 %
[EX A]: e

[EX Q]: Problem: alex takes a loan of $ 4,000 to buy a used truck at the rate of 6 % simple interest . calculate the annual interest to be paid for the loan amount .
Options: a ) 680 , b ) 700 , c ) 240 , d ) 620 , e ) 260
[EX A]: c

[EX Q]: Problem: if a lends rs . 3500 to b at 10 % per annum and b lends the same sum to c at 15 % per annum then the gain of b in a period of 3 years is ?
Options: a ) 525 , b ) 500 , c ) 510 , d ) 530 , e ) 550
[EX A]:
a