Machinability ratings are to be determined for a new work material using the cutting speed for a specified tool life as the basis of comparison. For the base material (B1112 steel), test data resulted in Taylor equation parameter values of n = 0.24 and C = 450, where speed is m/min and tool life is min. For the new material, the parameter values were n = 0.28 and C = 490. Cemented carbide tools were used. Compute machinability ratings for the new material using as the tool life criterion (a) 60 min, (b) 10-min, and (c) 1.0 min. (d) What do the results show about the difficulties in machinability measurement?