1. A boy pulls a boat a distance of 50.0 m along a dock using a rope that makes a 25.0 angle with the horizontal. How much work is done on the boat by the boy if he pulls with a force of 680 N on the rope?

2. One of the fastest and tallest roller coasters in the world is the Steel Dragon in Mie, Japan. The roller coaster has a speed of 3.0 m/s at the top of a hill. The ride includes a vertical drop of 93.5 m just after the hill. Neglecting friction, what is the speed of the riders at the bottom of the hill?

3. How much work must be done to stop a 1250 kg car traveling at 105 km/h?