17.22 A 22 factorial design has produced the following model relating ma- chined part surface finish to feed rate (x) and nose radius (x) of the tool (x, x are in coded units of 1): y = = 90 + 10x - 15x2 + 5xX. (a) What is the average surface finish across the experiment? (b) What are the values for E, E2, and E12 as obtained from the experiment? (c) Sketch the response surface in the X, X, y coordinate space. (d) What value for the surface finish does the model predict when the feed rate and nose radius are at their high levels for the experiment? (e) If a surface finish of 85 is desired, what value of feed rate (coded units) should be used if the nose radius takes on the low level used in the experiment? 17.23 Apply the respon