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

Example Input: Problem: a certain cube floating in a bucket of water has between 75 and 85 percent of its volume below the surface of the water . if between 9 and 16 cubic centimeters of the cube ' s volume is above the surface of the water , then the length of a side of the cube is approximately 
Options: ['a ) 4', 'b ) 5', 'c ) 7', 'd ) 8', 'e ) 9']
Example Output: a

Example Input: Problem: if circles x and y have the same area and circle x has a circumference of 12 π , half of the radius of circle y is : 
Options: a ) 16 , b ) 8 , c ) 3 , d ) 2 , e ) 1
Example Output: c

Example Input: Problem: a perfect square is defined as the square of an integer and a perfect cube is defined as the cube of an integer . how many positive integers n are there such that n is less than 30,000 and at the same time n is a perfect square and a perfect cube ? 
Options: a ) 4 , b ) 5 , c ) 6 , d ) 7 , e ) 8
Example Output:
b