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A sled of mass m is coasting at a constant velocity on the ice covered surface of a lake. Four birds, with a combined mass 0.75m, gently land at the same time on the sled. The sled and birds continue sliding along the original direction of motion. How does the kinetic energy of the sled and birds compare with the initial kinetic energy of the sled before the birds landed? O The final kinetic energy is one half (1/2) of the initial kinetic energy. O The final kinetic energy is two thirds (2/3) of the initial kinetic energy. O The final kinetic energy is four seventh (4/7) of the initial kinetic energy. The final kinetic energy is one quarter (1/4) of the initial kinetic energy. O The final kinetic energy is one ninth (1/9) of the initial kinetic energy.Two identical automobiles have the same speed, one traveling east and one traveling west. Do these cars have the same momentum? Yes, because they have the same mass and speed. Yes, because they have the same mass and velocity. O No, because they have the same mass but not the same speed. O No, because they have the same mass but not the same velocity