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: a man has $ 10,000 to invest . he invests $ 4000 at 5 % and $ 3500 at 4 % . in order to have a yearly income of $ 500 , he must invest the remainder at : 
Options: a ) 4.6 % , b ) 3.6 % , c ) 6.4 % , d ) 7.8 % , e ) 8.9 %

A: c
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Q: Problem: an error 6 % in excess is made while measuring the side of a square . the percentage of error in the calculated area of the square is : 
Options: a ) 12.36 , b ) 8.36 , c ) 9.36 , d ) 10.36 , e ) 11.36

A: a
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Q: Problem: in a certain company , a third of the workers do not have a retirement plan . 10 % of the workers who do not have a retirement plan are women , and 40 % of the workers who do have a retirement plan are men . if 120 of the workers of that company are men , how many of the workers are women ? 
Options: a ) 80 , b ) 95 , c ) 105 , d ) 120 , e ) 91

A:
e
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