The bumper cars at the state fair have identical 1.0-m-long horizontal springs protruding from the front of each car. A 250 kg car traveling at 1.5 m/s has a head-on collision with a 150 kg car traveling at 2.5 m/s in the opposite direction. The two springs are each compressed by 19 cm when the cars are instantaneously at rest, just before they rebound.What is the spring constant of the springs?