In a mechanical coal-wash process a portion of the inorganic sulfur and ash material in the coal can be removed. A feed stream to the process consists of 73% coal, 11% ash, 11% sulfur and 5% water. The clean-coal side of the process consists of 88% coal,6% sulfur, 3% ash and 3% water. The refuse side consists of 32% sulfur with the remainder being ash coal and water. If 80metric tons/hour of clean coal is required, determine the feed rate necessary for the mined coaland composition of the refuse material.