Which bounces higher a warm tennis ball or a regular tennis ball?

Question

and why does it

Answer 1

Presumably the warm tennis ball.  The air in the ball is  pressurized, providing the bounce.  Warming the ball will increase the internal pressure.  With higher internal pressure the ball should bounce higher.  But it would depend a great deal on the temperature difference.  Being a little warmer my have little effect, and may not out bounce just the normal variation among balls.

Answer 2

Must be a warm tennis ball - Jehen has said it all!