A box-shaped piece of granite measures 7 ft by 3 ft by 0.8 ft. (Enter your answers in lb.) (a) What is its weight? 2621 Incorrect: Your answer is incorrect. lb (b) Find the buoyant force that acts on it when it is submerged in water. (Enter the magnitude.) lb (c) What is the net force on the concrete piece when it is underwater? (Enter the magnitude.) lb