An external turning operation is performed on a hollow workpiece with a 200 mm external diameter and a 100 mm inner diameter, at a cutting speed of 40 m/min, a depth of cut of 2 mm, and a feed of 0.20 mm/rev. Calculate: the rotational speed for this workpiece, the machining time needed for a length of 250 mm, the material removal rate used, the parting-off time needed if the cross feed is 0.1 mm/rev, the expected tool life if the constants in the Taylor Formula are n = 0.23 and C = 240, and the maximum number of workpieces that could be produced under the given cutting conditions before the tool needs re-sharpening.