Jim, the Head of the Technology Center, Wants to Determine

Jim, the head of the technology center, wants to determine if any of the technicians are not performing as expected. He has initiated a service request tracking program to record the number of calls answered per shift by each technician. For each day last week, he recorded the following data:

Number of Service Requests Processed
$\begin{array} { | l | c | c | c | c | } \hline \text { Day } & \text { Worker 1 } & \text { Worker 2 } & \text { Worker 3 } & \text { Worker 4 } \\\hline \text { Monday } & 46 & 44 & 46 & 48 \\\hline \text { Tuesday } & 46 & 42 & 38 & 42 \\\hline \text { Wednesday } & 40 & 38 & 40 & 42 \\\hline \text { Thursday } & 36 & 38 & 40 & 38 \\\hline \text { Friday } & 36 & 40 & 44 & 40 \\\hline\end{array}$
A) Calculate all sample means and the mean of all sample means.
B) Calculate upper and lower control limits for this dataset.
C) Are any of the technicians over-performing or under-performing?