A couple MB of magnitude 2 lb ⋅ ft is applied to the drive drum B of a portable belt sander to maintain the sanding belt C at a constant speed. The total downward force exerted on the wooden work piece E is 12 lb, and μ k = 0.10 between the belt and the sanding platen D. Knowing that μs = 0.35 between the belt and the drive drum and that the radii of drums A and B are 1.00 in., determine

(a) The minimum tension in the lower portion of the belt if no slipping is to occur between the belt and the drive drum,

(b) The value of the coefficient of kinetic friction between the belt and the work piece.