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: find the compound interest on $ 50000 in 2 years at 4 % per annum , the interest being compounded half - yearly ? 
Options: a ) $ 645.56 , b ) $ 4121.60 , c ) $ 954.26 , d ) $ 745.69 , e ) $ 1020.45
[A]: b


[Q]: Problem: a shopkeeper sold an article at $ 100 with 10 % profit . then find its cost price ? 
Options: a ) $ 120 , b ) $ 100 , c ) $ 91 , d ) $ 72 , e ) $ 69
[A]: c


[Q]: Problem: a shopkeeper sold an article for rs 2564.36 . approximately what was his profit percent if the cost price of the article was rs 2300 
Options: a ) 4 % , b ) 5 % , c ) 6 % , d ) 7 % , e ) 12 %
[A]:
e