A box with mass 10.0 kg moves on a ramp that is inclined at an angle of 55.0^o above the horizontal. The coefficient of kinetic friction between the box and the ramp surface is µ_k = 0.300. Calculate the magnitude of the acceleration of the box if you push on the box with a constant force F = 120.0 N that is parallel to the ramp surface and

(a) Directed down the ramp, moving the box down the ramp;

(b) Directed up the ramp, moving the box up the ramp.