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: a father said to his son , ` ` i was as old as you are at the present at the time of your birth ' ' . if the father ' s age is 52 years now , the son ' s age 5 years back was : 
Options: a ) a ) 14 , b ) b ) 67 , c ) c ) 56 , d ) d ) 21 , e ) e ) 34

A: d
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Q: Problem: tara bought 19 cartons of ice cream and 4 cartons of yoghurt . each carton of ice cream cost $ 7 and each carton of yoghurt cost $ 1 . how much more did tara spend on ice cream than on yoghurt ? 
Options: a ) $ 144 , b ) $ 130 , c ) $ 80 , d ) $ 110 , e ) $ 129

A: e
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Q: Problem: at the end of the month , a certain ocean desalination plant ’ s reservoir contained 14 million gallons of water . this amount is twice the normal level . if this amount represents 70 % of the reservoir ’ s total capacity , how many million gallons short of total capacity is the normal level ? 
Options: a ) 2 , b ) 5 , c ) 10 , d ) 12 , e ) 15

A:
c
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