A billiard ball travels 25 cm in the positive direction, hits the cushion and rebounds in the negative direction, and finally comes to rest 6.0 cm behind its original position. 1. What is the distance covered by the ball?
Express your answer to three significant figures and include the appropriate units.

2. What is the displacement of the ball?

An engineer designs a roller coaster so that a car travels horizontally for 152 ft, then climbs 137 ft at an angle of 34.0° above the horizontal. it then moves 137 ft at an angle of 48.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)

Which of the following are appropriate acceleration units?

How to tell if two objects are in thermal equilibrium 1.the objects have the same temperature 2.the objects are the same size 3.the objects are touching each other 4.the objects temperatures are changing