Answer:
about 13.8 in³
Step-by-step explanation:
The volume of air is the difference between the volume of the cylinder of radius 1.3 inches and height 7.8 inches, and that of three spheres, each with a radius of 1.3 inches.
The formula for the volume of a cylinder is ...
V = πr²h
The formula for the volume of a sphere is ...
V = (4/3)πr³
For h = 6r, the difference is ...
(cylinder volume) - 3×(sphere volume) = πr²·(6r) - 3×(4/3)πr³
= πr³(6 -4)
= 2πr³ = 2π(1.3 in)³ = 4.394π in³
≈ 13.8 in³ . . . . air space in the cylinder of tennis balls
