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Glucose is diffusing at 25 degrees centigrade in water within a porous medium having a porosity of 0.5, tortuosity of 1.8 and average pore diameter of 8.6x 10 microns. Determine the steady state flux of glucose between two points within the medium separated by a distance of 1 mm and having concentrations 1.5 g/1 and 1.51 g/l respectively