6. A 3000 kg red truck moving to the right at 12 m/s is struck by a 1000 kg yellow car moving to the left at 30 m/s. The vehicles stick together after the collision. a. Calculate the final speed of the two cars AFTER the collision, and indicate their direction. (Hint: Draw a diagram showing before and after to help you!) b. Calculate the total kinetic energy before and after the collision. Is this collision elastic or (inelastic