A 330-kg piano slide 3.6m down a 28o incline and is kept from accelerating by a man who is pushing back on it parallel to the incline (Fig. 6-36). The effective coefficient of kinetic friction is 0.40. Calculate:
(a) The force exerted by the man,
(b) The work done by the man on the piano,
(c) The work done by the friction force,
(d) The work done by the force of gravity, and
(e) The net work done on the piano.