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: if a ' s salary is 20 % less than b ' s salary , by how much percent is b ' s salary more than a ' s ? 
Options: a ) 5 % , b ) 10 % , c ) 15 % , d ) 25 % , e ) none

A: d
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Q: Problem: what is the average of first 21 multiples of 6 ? 
Options: a ) a ) 66 , b ) b ) 77 , c ) c ) 79 , d ) d ) 81 , e ) e ) 82

A: a
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Q: Problem: when asked what the time is , a person answered that the amount of time left is 1 / 3 of the time already completed . what is the time . 
Options: a ) 2 pm , b ) 9 pm , c ) 3 pm , d ) 8 pm , e ) 6 pm

A:
e
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