Which best summarizes a concept related to the work-energy theorem? when work is positive, the environment does work on an object. when work is negative, the environment does work on an object. when work is positive, the kinetic energy in a system remains constant. when work is negative, the kinetic energy in a system remains constant.

On a frictionless air track, a blue glider with mass 0.200 kg is moving to the right with a speed of 8.00 m/s. it strikes a red glider that has mass 0.600 kg and that is initially at rest. after the collision, the blue glider is moving to the left with a speed of 3.00 m/s.(a) what are the magnitude and direction of the velocity of the red glider after the collision? (b) is this collision elastic?