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: jacob is 39 years old . he is 3 times as old as his brother . how old will jacob be when he is twice as old ? 
Options: a ) 63 , b ) 64 , c ) 65 , d ) 76 , e ) 67

A: c
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Q: Problem: a ferry can transport 50 tons of vehicles . automobiles range in weight from 1600 to 3200 pounds . what is the greatest number of automobiles that can be loaded onto the ferry ? 
Options: a ) 23 , b ) 41 , c ) 48 , d ) 62 , e ) 86

A: d
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Q: Problem: how many three - element subsets of { 1,2 , 3,4 } are there that do not contain the pair of elements 2 and 4 ? 
Options: a ) 1 , b ) 2 , c ) 3 , d ) 4 , e ) 5

A:
b
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