In a surface grinding operation the wheel diameter = 150 mm and the depth = 0.07 mm. The wheel speed = 1450 m/min, work speed = 0.25 m/s, and grinding width = 5 mm. The number of active grits per area of wheel surface = 0.75 grits/mm2. If the grain aspect ratio is 15, determine (a) the chip thickness, (b) metal removal rate, and (c) number of chips formed per unit time for the portion of the operation when the wheel is engaged in the work.