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: cost is expressed by the formula tb ^ 4 . if b is doubled , the new cost is what percent of the original cost ? 
Options: a ) 200 , b ) 600 , c ) 800 , d ) 1600 , e ) 50

A: d
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Q: Problem: a collection of books went on sale , and 2 / 3 of them were sold for $ 2.25 each . if none of the 40 remaining books were sold , what was the total amount received for the books that were sold ? 
Options: a ) $ 160 , b ) $ 150 , c ) $ 280 , d ) $ 200 , e ) $ 180

A: e
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Q: Problem: 4.509 / 10.02 = 
Options: a ) 0.45 , b ) 0.3505 , c ) 0.3509 , d ) 0.351 , e ) 0.3527

A:
a
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