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 milk man has 15 liters of milk . if he mixes 5 liters of water , which is freely available , in 20 liters of pure milk . if the cost of pure milk is rs . 18 per liter , then the profit of the milkman , when he sells all the mixture at cost price is : 
Options: a ) 20 % , b ) 25 % , c ) 33.33 % , d ) 18 % , e ) none of these

A: a
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Q: Problem: the current birth rate per certain number of people is 52 , whereas corresponding death rate is 16 per same number of people . if the net growth rate in terms of population increase is 1.2 percent , find number of persons . ( initally ) 
Options: a ) 4000 , b ) 2000 , c ) 3000 , d ) 5000 , e ) 1000

A: c
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Q: Problem: at what rate percent on simple interest will rs . 750 amount to rs . 975 in 5 years ? 
Options: a ) 2 , b ) 3 , c ) 4 , d ) 5 , e ) 6

A:
e
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