A cylinder has a surface area of 312π ft.2 . If its height is 20 ft., what is the measure of its radius?(1 point)
Responses
6 ft.
6 ft.
5.5 ft.
5.5 ft.
5 ft.
5 ft.
6.5 ft.
Responses
6 ft.
6 ft.
5.5 ft.
5.5 ft.
5 ft.
5 ft.
6.5 ft.