I need help understanding the steps, I am lost on this unit!

5. A rock is dropped a distance of 4 m. The mass of the rock is 2 kg. How fast will it be going when it reaches the ground? 6. A bowling ball is rolled across the floor at a velocity of 2.0 m/s. The mass of the ball is 6 kg. If the ball rolls up a ramp and stops, how high will it get? 7. What has more kinetic energy, a dump truck moving at 20 m/s, or a car moving at 20 m/s? 8. A boy lifts a 2.2 kg book from his desk, which is 0.80 m high, to a bookshelf that is 2.10 m high. What is the potential energy of the book relative to the desk? 9. To increase an objects potential energy, what must you do to the object? 10. A ball is place at the top of an incline. The ball is 0.5 m above the ground. The ball rolls down the incline and picks up speed. How fast will it be going when it reaches the bottom of the incline? The mass of the ball is unknown. 1 1. A bullet is fired straight up from a gun. The mass of the bullet is 0.010 kg and is moving at 600 m/s. How high will the bullet get? 12. When an object is thrown up, initially it starts with energy. As it increases in height, gravity does work to slow it down and when it gets to the top of its trajectory, and its velocity is zero, it has no energy. At the top though, gravity acts to pull it down, and hence we say it has energy. This energy will be changed to energy as the ball picks up speed and races to the ground. 13. If a 1.8 kg brick falls to the ground from a chimney that is 6.7 m high, how much Ug will it lose