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: a store ' s selling price of $ 2240 for a certain computer would yield a profit of 40 percent of the store ' s cost for the computer . what selling price would yield a profit of 60 percent of the computer ' s cost ?
Options: a ) $ 2400 , b ) $ 2464 , c ) $ 2560 , d ) $ 2732 , e ) $ 2800
[EX A]: c

[EX Q]: Problem: a total of $ 20,000 was invested in two certificates of deposit at simple annual interest rates of 6 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 ) 2 / 5 , c ) 1 / 2 , d ) 3 / 5 , e ) 3 / 4
[EX A]: d

[EX Q]: Problem: what was the principal , if at 12 % per annum the interest after 3 years amounted to rs . 5888 less than the sum lent ?
Options: a ) 9000 , b ) 3000 , c ) 5000 , d ) 1300 , e ) 9200
[EX A]:
e