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 long will a boy take to run round a square field of side 50 meters , if he runs at the rate of 10 km / hr ? 
Options: a ) 52 sec , b ) 45 sec , c ) 72 sec , d ) 25 sec , e ) 39 sec
[A]: c


[Q]: Problem: the current birth rate per certain number of people is 52 , whereas corresponding death rate is 16 per same number of people . if the net growth rate in terms of population increase is 1.2 percent , find number of persons . ( initally ) 
Options: a ) 4000 , b ) 2000 , c ) 3000 , d ) 5000 , e ) 1000
[A]: c


[Q]: Problem: the salary of a worker is first increased by 40 % and afterwards reduced by 40 % . what is the net change in the worker ' s salary ? 
Options: a ) 8 % decrease , b ) 8 % increase , c ) 16 % decrease , d ) 16 % increase , e ) no change
[A]:
c