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 annual installment will discharge a debt of rs . 1428 due in 3 years at 12 % simple interest ? 
Options: a ) 315 , b ) 345 , c ) 425 , d ) 335 , e ) none of them
[EX A]: c

[EX Q]: Problem: sam invested rs . 12000 @ 10 % per annum for one year . if the interest is compounded half - yearly , then the amount received by sam at the end of the year will be ? 
Options: a ) 13230.0 , b ) 12300.02 , c ) 16537.5 , d ) 15000.0 , e ) 16537.11
[EX A]: a

[EX Q]: Problem: if the simple interest on a certain amount in at 4 % rate 5 years amounted to rs . 2160 less than the principal . what was the principal ? 
Options: a ) 1500 , b ) 2500 , c ) 2700 , d ) 3200 , e ) 11500
[EX A]:
c