4. A given model of a large radar dish represents an area of opportunity in which nonconformities may occur.

(a) (6 marks) Determine the centerline and control limits for the appropriate control chart. Use Minitab to construct an appropriate control chard.

(b) (3 marks) Are there any indications of a lack of control? What are the indications and why do they indicate a lack of control?

(c) (6 marks) If the process is not in a state of statistical control, eliminate out-of-control points and reconstruct the control charts.

Assembly Noncon... 1 25 2 60 3 28 4 65 5 91 6 56 7 40 8 54 9 90 10 44 11 62 12 81 70 | | | 75 24 16 50 17 70 56 21 18 19 20 21 22 88 34 82 23 53 24 102 25 64