1. Given the following data, construct a 3o range control chart.
Day of Sample Sample Values
Saturday 22, 19, 20
Sunday' 21, 20, 17
Monday 16, 17, 18
Tuesday 20, 16, 21
Wednesday 23, 20, 20
Thursday 19, 16, 21
a. If Friday's results are 15,14, and 21, is the process in control?
b. Construct a 3o means control chart and determine if the process is still in control on Friday?