A packed bed is composed of crushed rock with a density of 175 lbm/ft3 of such a size and shape that the average ratio of surface area to volume for the particles is 50 in2/in3. The bed is 6 ft deep has a porosity of 0.3 and is covered by a 2 ft deep layer of water that drains by gravity through the bed. Calculate the flow rate of water through the bed, assuming it exits at 1 atmosphere pressure