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: when greenville state university decided to move its fine arts collection to a new library , it had to package the collection in 20 - inch by 20 - inch by 15 - inch boxes . if the university pays $ 1.20 for every box , and if the university needs 3.06 million cubic inches to package the collection , what is the minimum amount the university must spend on boxes ? 
Options: a ) $ 255 , b ) $ 275 , c ) $ 510 , d ) $ 612 , e ) $ 2,550

A: d
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Q: Problem: the average ( arithmetic mean ) of 4 positive integers is 50 . if the average of 2 of these integers is 35 , what is the greatest possible value that one of the other 2 integers can have ? 
Options: a ) 55 , b ) 65 , c ) 100 , d ) 109 , e ) 129

A: e
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Q: Problem: if a + b + c = 21 , what is the total number of non - negative integral solutions ? 
Options: a ) 223 , b ) 233 , c ) 240 , d ) 243 , e ) 253

A:
e
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