What is the unit of intensity of sound?

Avery hard rubber ball (m = 0.5 kg) is falling vertically at 4 m/s just before it bounces on the floor. the ball rebounds back at essentially the same speed. if the collision with the floor lasts 0.05 s, what is the average force exerted by the floor on the ball?

Rohit is trying to tune an instrument

The diagram shows four locations in the electric field of a positive point charge m. at which location is the electric potential the greatest.