3) The crate show below is pulled up the inclined surface by the winch. The mass of the crate is m=45kg and the dimension b = 0.15m. The coefficient of kinetic friction between the crate and the surface is = 0.4. The moment of inertia of the drum on which the cable is being wound, including the part of the cable already wound on the drum, is IA = 4 kg-m. If the motor exerts a couple M = 50Nm on the drum, what is the crate's acceleration? 20 b M