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 buys an article for $ 10 . and sells it for $ 30 . find the gain percent ? 
Options: a ) 25 % , b ) 50 % , c ) 20 % , d ) 150 % , e ) 300 %

A: e
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Q: Problem: a survey was sent to 95 customers , 7 of whom responded . then the survey was redesigned and sent to another 63 customers , 9 of whom responded . by approximately what percent did the response rate increase from the original survey to the redesigned survey ? 
Options: a ) 2 % , b ) 5 % , c ) 7 % , d ) 28 % , e ) 63 %

A: c
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Q: Problem: a merchant gets a 5 % discount on each meter of fabric he buys after the first 2,000 meters and a 7 % discount on every meter after the next 1,500 meters . the price , before discount , of one meter of fabric is $ 2 , what is the total amount of money the merchant spends on 6,000 meters of fabric ? 
Options: a ) $ 9,300 , b ) $ 10,400 , c ) $ 11,500 , d ) $ 12,600 , e ) $ 13,700

A:
c
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