9. A sports car travels on a straight road at 22.0 km/h and increases its speed to 57.0 km/h in
5.0 s. Find the car's acceleration in m/s?.

Arailroad car collides with and sticks to an identical railroad car that is initially at rest. after the collision, the total kinetic energy of the two cars is a) the same as before. b) half as much as before. c) one third as much as before. d) one fourth as much as before. e) twice as much as before.