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'.

Example Input: 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
Example Output: a

Example Input: Problem: a total of $ 20,000 was invested in two certificates of deposit at simple annual interest rates of 4 percent and 8 percent , respectively . if the total interest on the two certificates was $ 1,440 at the end of one year , what fractional part of the $ 20.000 was invested at the higher rate ? 
Options: a ) 3 / 8 , b ) 4 / 5 , c ) 1 / 2 , d ) 3 / 5 , e ) 3 / 4
Example Output: b

Example Input: Problem: an uneducated retailer marks all his goods at 50 % above the cost price and thinking that he will still make 25 % profit , offers a discount of 25 % on the marked price . what is his actual profit on the sales ? 
Options: a ) 12.50 % , b ) 13.50 % , c ) 14 % , d ) 14.50 % , e ) none
Example Output:
a