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 area of a triangle with base 6 cm is equal to the area of a square with side 6 cm , then the altitude of the triangle is 
Options: ['a ) 12 cm', 'b ) 10 cm', 'c ) 11 cm', 'd ) 15 cm', 'e ) 20 cm']
a

Problem: a rectangular field has to be fenced on three sides leaving a side of 20 feet uncovered . if the area of the field is 680 sq . feet , how many feet of fencing will be required ? 
Options: ['a ) 80 feet', 'b ) 85 feet', 'c ) 83 feet', 'd ) 88 feet', 'e ) 90 feet']
d

Problem: the length of a rectangle is 2 cm more than the width of the rectangle . the perimeter of the rectangle is 20 cm . find the length and the width of the rectangle . 
Options: ['a ) l = 2 , w = 9', 'b ) l = 5 , w = 8', 'c ) l = 6 , w = 4', 'd ) l = 1 , w = 7', 'e ) l = 2 , w = 3']

c