Suppose, After Developing the Control Chart, a Subgroup of Size

Multiple Choice

Suppose, after developing the control chart, a subgroup of size 4 yields a sample mean of 12.09 ounces and a range of 0.08. Which of the following statements is true?

A) The process is out of control on the x-bar chart but in control on the R chart.
B) The process is in control on the x-bar chart and out of control on the R chart.
C) Since 12.09 > 12.074, the process is in control on the x-bar chart.
D) Since 0.08 < 0.137, the process is out of control on the R chart.
E) Since 12.09 > 12.03, the process is in control on the x-bar chart.