Answer:
32 cubic inches of air are needed to fill it completely.
Explanation:
A basketball has the format of a sphere.
The volume of a sphere with radius r is given by the following equation:

In this question:
Radius of 4.5 inches. So the volume, in cubic inches, is:

The volume of the ball is 382 cubic inches.
350 cubic inches have already been filled.
So 382-350 = 32 cubic inches of air are needed to fill it completely.