Zce. A student's head is bent over her physics book . The head weighs p= 23 . IN and Is supported by the muscle force Fm exerted by the neck extensor muscle and by the Contact force Fc exerted at the atlantooccipital Joint . Given that the magnitude of Fm is CO. ON and is directed 35. 0 below the horizontal . ( a) Find the magnitude of the contact force Fc ( 10 ) Find the direction of the contact force . Fc . If the direction is below the horizontal, enter a negative value 28 . The Coefficient of static friction between block A and a horizontal floor is 0. 340, and the coefficient of static friction between block B and the floor is 0. 300. The mass of each block is 2. 00 - kq , and they are connected together by a cord ( a) if a horizontal force F pulling on block is is slowly increased , in a direction parallel to the connecting cord , until the block starts Sliding, what is the magnitude of F at the instant they start to slide? ( b. ) what is the tension in the cord connecting blocks A + B just before they start to slide