The 100-lb boy at A is suspended from the cable that passes over the quarter circular clif...

The 100-lb boy at A is suspended from the cable that passes over the quarter circular cliff rock. What horizontal force must the woman at A exert on the cable in order to let the boy descend at constant velocity? The coefficients of static and kinetic friction between the cable and the rock are µs = 0.4 and µk = 0.35, respectively.