A process has generated the output (in centimeters) listed in file XR20063.
a. For a series of samples, each with n = 4, construct and interpret the x-bar and range charts for this process. Does it appear to be in control?
b. Given your response to part (a), is it appropriate to compute the Process Capability Index (Cpk) for this process? If so, determine the overall mean and standard deviation for all the units measured, then compute and interpret the Process Capability Index if the specification limits are USL = 5.700 centimeters and LSL = 5.100 centimeters.