1. The problem statement, all variables and given/known data a) A 0.25 kg pine cone falls from a branch 20 m above the ground. if it actually hits the ground with a speed of 9.0m/s, what was the average force of air resistance exerted on it? b) For the pulley system illustrated to the right, when the masses are released, what is the final speed of the 12kg mass just before it hits the floor? * the diagram is basically a 4.0 kg box at rest on the floor with a rope attached to it, the rope is thrown over a pulley, and attached to the hanging 12 kg box. the total distance that the 12 kg box travels is 5.0m. 2. Relevant equations i have for a) W = F d and for b) Ep = mgh, Ek = 1/2mv^2 3. The attempt at a solution i have no idea how to get started.