The velocity a rocket must reach to establish an orbit around earth is called escape velocity. true or false

With i really need the correct answer!

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 ?

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?