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: 54671 - 14456 - 35466 = ? 
Options: a ) 2449 , b ) 5449 , c ) 6749 , d ) 6449 , e ) 4749

A: e
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Q: Problem: a retailer bought a hat at wholesale and marked it up 60 % to its initial price of $ 24 . by how many more dollars does he need to increase the price to achieve a 100 % markup ? 
Options: a ) 3 , b ) 4 , c ) 5 , d ) 6 , e ) 7

A: d
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Q: Problem: what is the units digit of ( 3 ^ 5 ) ( 4 ^ 13 ) ? 
Options: a ) 2 , b ) 4 , c ) 6 , d ) 7 , e ) 8

A:
a
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