Suppose that a quality characteristic is normally distributed with specifications at 100 20. The process standard deviation is 6. (a) Suppose that the process mean is 100. Calculate C, and Cpk and interpret these ratios. What fraction of parts do you expect to be defective? (b) Suppose that the process mean is 106. Calculate C, and Cpk and interpret these ratios. What fraction of parts do you expect to be defective?