In this task, you need to answer the given multiple-choice question on geometry. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: tough and tricky questions : number properties . what is the smallest positive integer x such that 1512 x is the cube of a positive integer ? 
Options: a ) 7 , b ) 14 , c ) 28 , d ) 35 , e ) 49

A: e
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Q: Problem: a larger cube has 64 cubic inch as a volume and in the cube there are 64 smaller cubes such that their volume is 1 cubic inch . what is the difference between the surface areas ’ sum of the 64 smaller cubes and the surface area of the larger cube , in square inch ? 
Options: a ) 54 , b ) 64 , c ) 81 , d ) 288 , e ) 120

A: d
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Q: Problem: if the sum of a number and its square is 72 , what is the number ? 
Options: a ) 15 , b ) 26 , c ) 8 , d ) 91 , e ) none of these

A:
c
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