A 250-N force is directed horizontally as shown to push a 29-kg box up an inclined plane at a constant speed. Determine the magnitude of the normal force, FN, and the coefficient of kinetic friction, µk. So, I know I have to find the vertical and parallel forces Vertical: Fn and 250 sin of angle (where is the angle symbol???) so, if you look at the second picture, that is where I get stucked. Is "mg" also part of the parallel force?