Two buses have equal masses (5,000 kg). Bus A is moving at a velocity of 20 m/s west. Bus B is at rest. When they collide, Bus B bounces off of Bus A. After they collide, Bus A has 0 momentum. What is the final momentum of Bus B? A.) 250 kg m/s west
B.) 105,000 kg m/s west
C.) 0 kg m/s west
D.) 100,000 kg m/s west