In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: what is the minimum percentage increase in the mean of set f { - 4 , - 1 , 0 , 6 , 9 } if its two smallest elements are replaced with two different primes ? 
Options: a ) 25 % , b ) 50 % , c ) 75 % , d ) 100 % , e ) 200 %

A: d
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Q: Problem: find the number which multiplied by 15 is increased by 196 . 
Options: a ) 14 , b ) 20 , c ) 26 , d ) 28 , e ) 27

A: a
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Q: Problem: a number is doubled and 15 is added . if resultant is trebled , it becomes 75 . what is that number 
Options: a ) 8 , b ) 10 , c ) 5 , d ) 14 , e ) 7

A:
c
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