An elevated cylindrical shaped water tower is in require of paint. If the radius of the tower is 10 ft and the tower is 40 ft tall, what is the net area to be painted? (π = 3.14)

a. 1,570 ft²

b. 2,826 ft²

c. 2,575 ft²

d. 3,140 ft²

b. To determine the surface area of a cylinder, use the following formula: surface area = 2πr² + πdh. Thus, the surface area = 2(3.14)(10)² + (3.14)(20)(40) or 3,140 ft². If you select b, you found the surface area of the circular top and forgot about the bottom of the water tower. Thus, the bottom of the tower could need painting since the tank is elevated.