A box with mass 13.0 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 ?k = 0.300. Choose the x-axis along the surface of the ramp and the y-axis perpendicular to the surface. A. Calculate the magnitude of the acceleration of the box if you push on the box with a constant force 180.0 N that is parallel to the ramp surface and directed down the ramp, moving the box down the ramp.
B. Calculate the magnitude of the acceleration of the box if you push on the box with a constant force 180.0 N that is parallel to the ramp surface and directed up the ramp, moving the box up the ramp.