Telecom manufactures electronic components for computers. One measure it uses to monitor the quality of its distribution process is

the number of customer invoice errors. The distribution center manager monitored the company's order processing and distribution

by recording the number of invoice errors for $30$ days. The sample results are as follows:

Construct a c$-$chart with $3$ limits for invoice errors and indicate if the process was out of control at any time.

$($Round answers to $2$ decimal places, e$.$g$.5\mathrm{.}25.)$

Using $3$ control limits$,$ what is the average number of invoice errors?

What is the $3$ upper control limit$?$

Is the process in control?