1. The problem statement, all variables and given/known data A 280-kg piano slides 4.3 m down a 30 degree incline and is kept from accelerating by a man who is pushing back on it parallel to the incline. The effective coefficient of kinetic friction is .400. 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. 2. Relevant equations W=Fd.... ? 3. The attempt at a solution I know it's a long problem... I don't know how to find the work done by each force.