Q4. A facing operation is performed on an engine lathe. The diameter of the cylindrical part is 60mm and the length is 150mm. The spindle rotates at a speed of 180rev/min. Depth of cut 1mm, and feed 0.8mm/ rev. Assume the cutting tool moves from the outer diameter of the workpiece to exactly the center at a constant velocity. Determine (a) the velocity of the tool as it moves from the outer diameter towards the center and (b) the cutting time