The radius of a cone-shaped tank is 4 feet less than its height. if the height of the tank is (x - 3) feet, the expression below shows the volume of the tank.

1 over 3_ (x - 7)2 (x - 3)

what does the factor 1 over 3(x - 7) represent?

the total surface area of the tank

one third of the radius of the tank

one third of the height of the tank

the total area of the base of the tank