Which of these lab safety procedures is incorrect? a) no horseplay in the lab. b) follow instructions as given by teacher. c) know the fire escape route from your lab. eliminate d) always carry a textbook into the lab for checking accuracy.

Abumper car with a mass of 250 kg is traveling at a speed of 4 m/s. this bumper car collides and sticks to a second bumper car with a mass of 250 kg, which is initially at rest. what is the final speed of these two bumper cars after the collision, assuming they remain stuck together?