Which statement best describes how light waves travel in a uniform medium. a. in straight lines. b. in extending circles. c. in bent lines. d. in shrinking ripples

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?