Problem 4 Three cables are connected at D, where an upward force of 30 kN is applied. Determine the tension in each cable. Problem 5 A 300-N force is applied atA as shown. Determine (a) the moment of the 300-N force about D, (b) the smallest force applied at B that creates the same moment about D. Problem 6 Rod AB is held in place by the cord AC. Knowing that c = 840 mm and that the moment about 3 of the force exerted by the cord at point A is 756 N-m, determine the tension in the cord