The paper towel dispenser carries two rolls of paper. The one in use is called the stub...

The paper towel dispenser carries two rolls of paper. The one in use is called the stub roll A and the other is the fresh roll B. They weigh 2 lb and 5 lb, respectively. If the coefficients of static friction at the points of contact C and D are (μ_s)_c = 0.2 and (μ_s)_D = 0.5, determine the initial vertical force P that must be applied to the paper on the stub roll in order to pull down a sheet. The stub roll is pinned in the center, whereas the fresh roll is not. Neglect friction at the pin.