A quality analyst wants to construct a control chart for controlling a packaging process. Each day last week, he randomly selected four packages and weighted each, The data from that activity appear below:

Day	Package one	Package two	Package three	package four
Monday	23	22	23	24
Tuesday	23	21	25	21
Wednesday	24	23	25	28
Thursday	18	19	20	19
Friday	18	20	22	20

A.) What is the mean of all the sample means?

B.) Calculate upper and lower 3-sigma x-bar chart control limits that allow for natural variations

C.) Based on the x-bar chart, is this process in control?

D.) Calculate upper and lower limits for R-chart

E.) Is the range chart in control?