Someone please help, show the graph too when you used excel. I think that'$\text{'}$s where I got stuck. Thanks The thickness of a printed circuit board is an important quality parameter. Data on board

thickness $($in inches$)$ are given in the following table for $25$ samples of three boards each.

$($a$)$ Set up $x-$bar and $R$ control charts for $=0\mathrm{.}0027.$ Is the process in statistical control?

Please draw a plot.

$($b$)$ Set up $x-$bar and $S$ control chart, and compare the $S$ chart with the $R$ chart in part $($a$).$

Please draw a plot. Hint: In this case, you should re$-$estimate the variance of $x-$bar and re$-$

calculate the x$-$bar chart.