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: if the length of the longest chord of a certain circle is 10 , what is the radius of that certain circle ? 
Options: ['a ) 2.5', 'b ) 5', 'c ) 10', 'd ) 15', 'e ) 20']
[EX A]: b

[EX Q]: 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 25 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 ) 25 % , c ) 10 % , d ) 45 % , e ) 180 %
[EX A]: d

[EX Q]: Problem: a rectangular cube has sides measuring 3 inches long by 2 inches wide by 0.5 inches high . if the surface area of the rectangle is the same as a cube , what do the sides / walls of the cube measure ? round to the nearest whole number . 
Options: ['a ) 4', 'b ) 5', 'c ) 6', 'd ) 7', 'e ) 2']
[EX A]:
e