Two masses are connected by a string which passes over a pulley with negligible mass and friction. One mass hangs vertically and one mass slides on a horizontal surface. The horizontal surface has a coefficient of kinetic friction of 0.200. The vertically hanging mass is 3.00 kg and the mass on the horizontal surface is 3.00 kg. The magnitude of the acceleration of the vertically hanging mass is (the initial velocity of the horizontal mass is to the right)