Studies on a machine that molds plastic water pipe indicate that when it is injecting 1-inch diameter pipe, the process standard deviation is 0.05 inches. The one-inch pipe has a specification of 1-inch plus or minus 0.10 inch. What is the process capability index (Cp) if the long-run process mean is 1 inch? A Quality Analyst wants to construct a control chart for determining whether three machines, all producing the same product, are under control with regard to a particular quality variable. Accordingly, he sampled four units of output from each machine, with the following results: Machine Measurements 17 15 15 17 16 25 18 25 23 # 1 # 2 # 3 24 23 22 What are the x-bar chart three sigma upper and lower control limits?