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 $ 20000 in 2 years at 4 % per annum , the interest being compounded half - yearly ? 
Options: a ) $ 645.56 , b ) $ 1648.64 , c ) $ 954.26 , d ) $ 745.69 , e ) $ 1020.45

A: b
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Q: Problem: a technician makes a round - trip to and from a certain service center by the same route . if the technician completes the drive to the center and then completes 50 percent of the drive from the center , what percent of the round - trip has the technician completed ? 
Options: a ) 70 , b ) 65 , c ) 60 , d ) 75 , e ) 80

A: d
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Q: Problem: solve the quickfire maths brain teaser â ˆ š 36 % = ? 
Options: a ) 30 % , b ) 40 % , c ) 60 % , d ) 19 % , e ) 29 %

A:
c
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