A box with mass 12.0 kg moves on a ramp that is inclined at an angle of 55.0 above the horizontal. The coefficient of kinetic friction between the box and the ramp surface is uk = 0.300. Part A Calculate the magnitude of the acceleration of the box if you push on the box with a constant force 140.0 N that is parallel to the ramp surface and directed down the ramp, moving the box down the ramp. Express your answer with the appropriate units. HA (41 - Value Units Submit Request Answer Part B Caiculate the magritude of the acceleration of the box if you push on the box with a constant force 140.0 N that is paraliel to the ramp surtace and directed up the ramp, moving Ihe box up the ramp. Express your answer with the appropriate units. HA ? ... 12 = Value Units Submit Request Answer