Construct the appropriate control chart for the 11 observations, and determine if the process is in control using two sigma limits. No. of defects per unit for the observations are: 9, 4, 5, 6, 1, 8, 1, 9, 9, 3, 2.

Select one:

a.

2 observations out of control

b.

1 observation out of control

c.

3 observations out of control

d.

Under control