A railroad car moving at a speed of 3.28 m/s overtakes, collides and couples with two coupled railroad cars moving in the same direction at 1.40 m/s. All cars have mass of mass 1.8 x 104 kg. (a) Determine the speed (in m/s) of the three coupled cars after the collision. (Give your answer to at least 2 decimal places.) m/s (b) Determine the kinetic energy (in J) lost in the collision. Knowing the mass of each car and its speed before and after the collision, can you determine the initial and final kinetic energy and then the kinetic energy lost in the collision? J