A tennis ball is flying horizontally across the net. Air resistance is not negligible. Identify the forces on the ball

Answer 1

Well...if you said air resistance is not negligible, then it has to be one of those forces...
Anyway...heres my list:
- air resistance
- gravity

(These are only when its in air, if its not you could say the tennis racket when it got hit or the ground/court when it hits the ground)