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: if rs . 420 amount to rs . 540 in 4 years , what will it amount to in 6 years at the same rate % per annum ? 
Options: a ) s . 575 , b ) s . 595 , c ) s . 590 , d ) s . 600 , e ) s . 585

A: d
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Q: Problem: of 600 surveyed students , 20 % of those who read book a also read book b and 25 % of those who read book b also read book a . if each student read at least one of the books , what is the difference between the number of students who read only book a and the number of students who read only book b ? 
Options: a ) 20 , b ) 25 , c ) 30 , d ) 35 , e ) 75

A: e
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Q: Problem: the value of a machine depreciates at 23 % per annum . if its present value is $ 1 , 50,000 , at what price should it be sold after two years such that a profit of $ 24,000 is made ? 
Options: a ) $ 252935 , b ) $ 432935 , c ) $ 122935 , d ) $ 112935 , e ) $ 152935

A:
d
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