A process that is considered to be in control measures an ingredient in ounces. Below are the last 5 samples (each of size n = 5) taken. The population process standard deviation is 1.36.

Sample	Observations
1	9, 8, 10, 10, 11
2	13, 12, 12, 14, 11
3	12, 10, 10, 9, 10
4	11, 10, 10, 11, 10
5	12, 9, 8, 11, 10

For each question, you must show both explanation (calculation) and the final answer.

(a) Find five sample means (five sample averages). Carry one decimal place.

(b) Find the X double-bar (X bar-bar). Carry two decimal places.

(c) With Z=3, what are the control limits (UCL & LCL) for the X-bar chart? Carry two decimal places.