A laboratory periodically conducts a review of its test results to verify their accuracy. Each day 100 tests are selected randomly and then re-tested using a more sophisticated but expensive procedure, and the results are documented. (Each re-test result is classified simply as accurate or inaccurate.) The table below shows re-test results for the previous 12 days. Day Sample size Number of inaccurate test results 1 100 2 2 100 1 3 100 0 4 100 3 5 100 0 6 100 0 7 100 2 8 100 1 9 100 0 10 100 2 11 100 4 12 100 3 a) Develop a control chart for proportion defective indicating the centerline, upper control limit and lower control limit. b) Is the process in control? c) Suppose on days 13 through 15 you took a random sample of 100 tests and found the following were inaccurate. Day # of Inaccurate tests results 13 3 14 2 15 6 Is the process in control?