Construct and interpret an R-chart for the data in Exercise13.11.
In E 13.11
The data in the following table were collected for the purpose of constructing an xÌ…-chart.

a. Calculate and plot the upper control limit and, if appropriate, the lower control limit.
b. Calculate and plot the A, B, and C zone boundaries on the R-chart.
c. Plot the sample ranges on the R-chart and determine whether the process is in control.

Sample Measurements 19.7 19.4 18.7 20.2 19.6 20.6 21.2 22.6 18.7 21.2 20.7 20.1 19.4 18.4 18.8 3 4 21.2 20.4 17.3 21.8 20.9 18.1 20.9 22.3 17.6 17.4 18.3 22.3 20.3 22.8 19.5 20.6 18.6 19.7 23.1 20.7 20.4 21.4 21.2 20.6 18.6 21.7 20.4 10 22.6 22.7 20.1 19.7 18.6 18.2 18.5 21.5 21.0 21.2 17.7 19.8 19.7 19.5 20.2 19.1 18.3 19.2 11 13 14 20.7 19.7 18.7 19.6 18.9 20.5 23.2 21.4 19.9 19.8 22.4 20.0 17.8 21.2 21.8 19.7 21.0 20.5 20.6 16.9