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: what is the rate percent when the simple interest on rs . 4000 amount to rs . 320 in 2 years ? 
Options: a ) 4 % , b ) 4.1 % , c ) 4.2 % , d ) 4.3 % , e ) 4.5 %

A: a
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Q: Problem: mahesh marks an article 15 % above the cost price of rs . 540 . what must be his discount percentage if he sells it at rs . 460 ? 
Options: a ) 18 % , b ) 21 % , c ) 25.9 % , d ) 19 % , e ) none of these

A: c
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Q: Problem: a man can row his boat with the stream at 16 km / h and against the stream in 12 km / h . the man ' s rate is ? 
Options: a ) 8 kmph , b ) 9 kmph , c ) 2 kmph , d ) 4 kmph , e ) 1 kmph

A:
c
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