A block is pressed against a vertical wall by a forceF, as the drawing shows.

This force can either push the block upward at a constant velocity or allow it to slide downward at a constant velocity. The magnitude of the force is different in the two cases, while the directional angleis the same. Kinetic friction exists between the block and the wall, and the coefficient of kinetic friction is0.270. The weight of the block is39.0 N, and the directional angle for the forceFis=42.0. Determine the magnitude ofFwhen the block slides(a)up the wall and(b)down the wall.