Two 8-kg blocks A and B resting on shelves are connected by a rod of negligible mass. Know...

Two 8-kg blocks A and B resting on shelves are connected by a rod of negligible mass. Knowing that the magnitude of a horizontal force P applied at C is slowly increased from zero, determine the value of P for which motion occurs, and what that motion is, when the coefficient of static friction between all surfaces is (a) µs = 0.40, (b) µs = 0.50.