An air duct in a stadium has a circular cross section with a radius of 15 inches and a length of 49 feet and is open at both ends. What is the volume of the duct, and how much paint (in square feet) is needed to paint the exterior of the duct?

240.56 ft³,384.895 ft²

Step-by-step explanation:

15 inches = 1.25 feet where 1 inch = 0.0833 feet

volume of the air duct = volume of a cylinder = πr²h

volume of the air duct = 3.142 * (1.25 ft) ² * 49 ft = 240.56 ft³

the exterior of the duct = curved surface area of a cylinder = 2πrh = 2 * 3.142 * 1.25 ft * 49 ft = 384.895 ft²