The quality$-$control plan for a certain production process involves taking samples of size $4.$ The results from the last $30$ samples can be summarized as follows:$3028=7125$ER$,=143\mathrm{.}7$S; $=62\mathrm{.}5$a$.$ Compute the $3$o control limits for the R chart.b$.$ Compute the $3$o control limits for the S chart.c$.$ Using the sample ranges, compute the $3$o control limits for the X chart.d$.$ Using the sample standard deviations, compute the $3$o control limits for the X chart.