Ten samples of size four were taken from a process, and their weights measured

Ten samples of size four were taken from a process, and their weights measured. The sample averages
and sample ranges are in the following table. Construct and plot an x-bar and R-chart using this data. Is the process in control?
Sample Mean Range 1 20.01 0.45 2 19.98 0.67 3 20.25 0.30 4 19.90 0.30 5 20.35 0.36 6 19.23 0.49 7 20.01 0.53 8 19.98 0.40 9 20.56 0.95 10 19.97 0.79
Sample
1
2
3
4
5
6
7
8
9
10

Mean
20.01
19.98
20.25
19.9
20.35
19.23
20.01
19.98
20.56
19.97

Range
0.45
0.67
0.3
0.3
0.36
0.49
0.53
0.4
0.95
0.79