An analyst has drawn twelve samples, each containing six sample points, from a process that produces a product. The diameter of each product in the samples was determined. The results were tabulated and sample means and ranges were computed. The results were: Sample 1 2 3 4 Sample Mean (in.) Range (in.) 10.012 0.009 10.007 0.014 9.991 0.007 10.006 0.026 9.997 0.016 9.999 0.012 10.001 0.008 10.005 0.013 9.995 0.015 10.001 0.011 10.003 0.014 10.006 0.009 6 7 8 9 10 11 12 a) Determine the upper and lower control limits and the overall means for x-charts and R-charts. b) Draw the charts and plot the values of the sample means and ranges. c) Do the data indicate a process that is in control? d) Why or why not