At what point will the currents that transfer heat throughout a gas cease to flow? a. when the substance changes state and becomes a liquid b. when the entire gas is a single temperature c. when the substance is very hot on top and cold beneath d. when the particles stop bumping into each other

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?