Answer: 108π inches squared
Explanation:
Formula : Area of sector =
where , r= radius and

Given : A certain car's windshield wiper has a total length of 22 inches. As the wiper pivots it clears a sector with a central angle of 120 degrees.
If only 18 inches of the wiper cleans the windshield, then we take radius of the range of wiper cleaining = 18 inches
The area of the windshield that is wiped during each swing = Area of the sector made by wiper of with a central angle of 120 degrees.

Hence, the area (in exact form) of the windshield that is wiped during each swing is 108π inches squared.