The 5-kg spring-loaded gun rests on the smooth surface. It fires a ball having a mass of 1 kg with a velocity of v = 6 m/s relative to the gun in the direction shown. Neglect the size of the gun. If the gun is originally at rest, determine the horizontal distance d the ball is from the initial position of the gun at the instant the ball strikes the ground at D. v=6m/s C B 30° d