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

[EX Q]: Problem: a rectangular field is to be fenced on three sides leaving a side of 20 feet uncovered . if the area of the field is 256 sq . feet , how many feet of fencing will be required ? 
Options: a ) 45.6 , b ) 40 , c ) 68 , d ) 88 , e ) 92
[EX A]: a

[EX Q]: Problem: if the volume of two cubes are in the ratio 64 : 8 , the ratio of their edges is : 
Options: a ) 3 : 1 , b ) 3 : 2 , c ) 3 : 5 , d ) 2 : 1 , e ) none of these
[EX A]: d

[EX Q]: Problem: the measurement of a rectangular box with lid is 25 cmx 6 cmx 18 cm . find the volume of the largest sphere that can be inscribed in the box ( in terms of π cm 3 ) . ( hint : the lowest measure of rectangular box represents the diameter of the largest sphere ) 
Options: ['a ) 288', 'b ) 48', 'c ) 36', 'd ) 864', 'e ) 964']
[EX A]:
c