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: the true discount on a bill of rs . 2460 is rs . 360 . what is the banker ' s discount ? 
Options: a ) rs . 432 , b ) rs . 422 , c ) rs . 412 , d ) rs . 442 , e ) none of these

A: b
****
Q: Problem: if it is assumed that 60 percent of those who receive a questionnaire by mail will respond and 900 responses are needed , what is the minimum number of questionnaires that should be mailed ? 
Options: a ) 1300 , b ) 1350 , c ) 1400 , d ) 1450 , e ) 1500

A: e
****
Q: Problem: each light bulb at a hotel is either incandescent or fluorescent . at a certain moment , forty percent of the incandescent bulbs are switched on , and eighty percent of the fluorescent bulbs are switched on . if 72 percent of all the bulbs are switched on at this moment , what percent of the bulbs that are switched on are incandescent ? 
Options: a ) 24 % , b ) 16 % , c ) 11 % , d ) 7 % , e ) 5 %

A:
c
****