How do I solve this Physics problem on force,friction, and angles?

Question

A mover is trying to pull a 2750N piano up an incline plane of 20°. If the coefficient of friction is 0.17, what force must the mover apply to the piano?

Answer 1

Normal force of piano onto inclined plane = 2750*cos(20) = 2584.2 N. Force of friction is (0.17)(2584.2) = 439.3 N.

Force of gravity pushing piano down the incline = 2750*sin(20) = 940.6 N. The mover must supply a minimum force equal to the force of friction and the force of gravity:

$Force=439.3+940.6=1379.9N$