Calculate the minimum velocity (m/sec) required to transport Coarse sand through a sewer of 35 cm diameter with sand particles of 0.97 mm diameter and specific gravity 2.59, and organic matter of 4.75 mm average size with specific gravity of 1.42. The friction factor for the sewer material may be assumed as 0.04 and roughness coefficient of 0.013. Consider k = 0.05 for inorganic solids and 0.07 for organic solids.