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

Problem: if the volume of a cube is x ^ 3 cubic units , what is the number of square units in the surface area of the cube ? 
Options: ['a ) x ^ 2', 'b ) x ^ 3', 'c ) x ^ 6', 'd ) 6 x ^ 2', 'e ) 6 x ^ 3']
d

Problem: the length of a rectangle is two - fifths of the radius of a circle . the radius of the circle is equal to the side of the square , whose area is 2500 sq . units . what is the area ( in sq . units ) of the rectangle if the rectangle if the breadth is 10 units ? 
Options: a ) 140 , b ) 150 , c ) 160 , d ) 170 , e ) 200
e

Problem: if the length of the sides of two cubes are in the ratio 6 : 1 , what is the ratio of their total surface area ? 
Options: a ) 6 : 1 , b ) 12 : 1 , c ) 24 : 1 , d ) 36 : 1 , e ) 72 : 1

d