You are a quality control manager and would like to determine if the process is in control or not. Suppose that the average weight of units is 10 and process standard deviation of the weights of units (standard deviation of original units) is 1. You use the significance level 0.26% (corresponding to z=3). How many observations exceed the upper control - lower control range?

A

0

B

1

C

2

D

4

E

5 or more

Sample 2 Unit1 12 Sample 1 8 8 10 10 9 Unit2 Unit3 Unit4 Sample Mean 9 9 Sample 3 Sample 4 10 12 19 11 7 9 8 Sample 5 11 14 11 12 10 11 10 11 12