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: what is the smallest positive integer nn such that √ 6,480 ∗ n is a perfect cube ? 
Options: a ) 5 , b ) 5 ^ 2 , c ) 30 , d ) 30 ^ 2 , e ) 30 ^ 4
Example Output: e

Example Input: Problem: sand is poured into a box so that the box is being filled at the rate of 3 cubic feet per hour . if the empty rectangular box is 5 feet long , 4 feet wide , and 3 feet deep , approximately how many hours does it take to fill the box ? 
Options: a ) 14 , b ) 16 , c ) 18 , d ) 20 , e ) 22
Example Output: d

Example Input: Problem: the length of each side of square a is increased by 100 percent to make square b . if the length of the side of square b is increased by 80 percent to make square c , by what percent is the area of square c greater than the sum of the areas of squares a and b ? 
Options: a ) 75 % , b ) 80 % , c ) 100 % , d ) 150 % , e ) 159.2 %
Example Output:
e