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: company a imported 10,500 widgets made of either brass or aluminum . the widgets are painted blue , red or green . if 10 percent of the widgets are made of brass and of those 20 percent are painted red and 40 percent are painted blue how many brass widgets painted green were imported ? 
Options: a ) 480 , b ) 840 , c ) 1050 , d ) 420 , e ) 2100

A: d
****
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: the present population of a town is 4032 . population increase rate is 20 % p . a . find the population of town before 2 years ? 
Options: a ) 2500 , b ) 2800 , c ) 3500 , d ) 3600 , e ) 2050

A:
b
****