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: evaluate 64 / . 08 
Options: a ) 800 , b ) 500 , c ) 505 , d ) none of these , e ) 506

A: a
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Q: Problem: the product of a and b is equal to 12 more than twice the sum of a and b . if b = 10 , what is the value of b - a ? 
Options: a ) 2 , b ) 5 , c ) 7 , d ) 6 , e ) 35

A: d
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Q: Problem: a pharmaceutical company received $ 2 million in royalties on the first $ 20 million in sales of and then $ 9 million in royalties on the next $ 108 million in sales . by approximately what percentage did the ratio of royalties to sales decrease from the first $ 20 million in sales to the next $ 108 million in sales ? 
Options: a ) 8 % , b ) 15 % , c ) 45 % , d ) 52 % , e ) 56 %

A:
b
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