A screw jack with a 1-in. double-thread Acme screw is used to raise a load of 10,000 lb. A plain thrust collar of 2.0 in. mean diameter is used. Coefficients of running friction are estimated as 0.13 and 0.10 for f and fe, respectively. (See Figure P10.6.) (a) Determine the screw pitch, lead, thread depth, mean pitch diame- ter, and helix angle. (b) Estimate the starting torque for raising and for lowering the load. (c) Estimate the efficiency of the jack when raising the load. d=2.0 in. fe 0.10- Weight = 10,000 lb FIGURE P10.6 Force F f= 0.13 -1-in. double-thread Acme screw