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'.

Problem: the difference between the compound interest compounded annually and simple interest for 2 years at 20 % per annum is rs . 72 . find the principal ? 
Options: a ) 2277 , b ) 2667 , c ) 3600 , d ) 2766 , e ) 1800
e

Problem: joe invested a certain sum of money in a simple interest bond whose value grew to $ 310 at the end of 3 years and to $ 410 at the end of another 5 years . what was the rate of interest in which he invested his sum ? 
Options: a ) 6 % , b ) 7 % , c ) 8 % , d ) 9 % , e ) 10 %
c

Problem: in an election , candidate a got 65 % of the total valid votes . if 15 % of the total votes were declared invalid and the total numbers of votes is 560000 , find the number of valid vote polled in favor of candidate . 
Options: a ) 330000 , b ) 309400 , c ) 347000 , d ) 356000 , e ) 357000

b