How do u find the number of electronic

Alead ball is dropped into a lake from a diving board 5m above the water . it hits the water with a certain velocity and then sink with constant velocity in bottom . it reaches the bottom 5 second after it is dropped if g= 10m/s2 . find depth of the lake and average velocity of the ball ?

What is the speed of an object at a given moment?

The earth exerts a gravitational force of 500 n on amy. what is amy’s mass in kg?