a sled with a mass of 8.00 kg moves in a straight line on a frictionless horizontal surface. At one point in its path, its speed is 4.00m/s after it has traveled 2.50m beyond this point its speed is 6.00m/s. Find the force acting on a sled assuming that this force is constant and that this force is constant and that it acts in the direction of sled's motion.