Five Samples Are Taken, with Five Observations Each ADetermine the Control Limits for the R-Chart

Five samples are taken, with five observations each. The sample findings are listed below. The sample values represent service times in minutes. ObservationNumber
$\begin{array}{|r|r|r|r|r|r|}\hline \frac{\text { Sample }}{\text { Number }} & 1 &2&3&4&5\\\hline 1 & 10.1 & 10.6 & 9.8 & 9.9 & 10.9 \\\hline 2 & 9.7 & 9.5 & 10.3 & 9.9 & 10.5 \\\hline 3 & 10.1 & 10.7 & 9.2 & 10.0 & 10.1 \\\hline 4 & 9.9 & 9.8 & 10.5 & 10.4 & 10.1 \\\hline 5 & 10.4 & 10.1 & 10.9 & 9.9 & 10.3 \\\hline\end{array}$
a.Determine the control limits for the R-chart.
b.Can it be concluded that the R-chart is in statistical control and proceed to develop the x-bar chart?