A face milling operation removes 6.0 mm from the top surface of a rectangular piece of aluminum that is 300 mm long by 90 mm wide by 75 mm thick. The cutter follows a path that is centered over the workpiece. It has four teeth and is 100 mm in diameter. Cutting speed = 2.0 m/s, and chip load = 0.27 mm/tooth. Determine (a) machining time and (b) maximum metal removal rate during cutting.