A 2100-kg car is traveling at 25 m/s when it crashes into the rear end of a 1650-kg
car traveling at 21 m/s in the same direction on nearly frictionless ice. The two cars
become stuck together and slide on the ice. How fast do the two cars move together
immediately after the collision?
A)22 m/s
B)23 m/s
C)21 m/s
D)18 m/s