Cars are designed with crumple zones, so that in a car crash much of the kinetic energy goes into deforming the structure of the car. What if car bumpers acted like large springs instead? In a head-on collision, this might bring the car to rest and then propel the car backwards without causing much damage to the car. If you were an engineer working for one of the big auto manufacturers, would you suggest such a spring-bumper system? Why or why not?