Physics Help (forces and angles)?

Pyramid workers were often tasked with balancing large slabs of stone. Take the case of five workers, equally sharing the force to tip a stone at an angle θ above the horizontal using a light rope. (a) If θ = 18.0°, what force must each worker be exerting on the rope? (your answer will be in terms of the mass m) (b) As the angle θ increases, assuming the workers do not change the angle of the rope, does the force required by each worker increase, decrease, or stay the same? (c) What angle (θcritical) do the workers have to apply zero force to balance the slab? What happens if this angle is exceeded?