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2. A machine produces bolts with an average length of 16 inches. A manager selects a...

2. A machine produces bolts with an average length of 16 inches. A manager selects a sample of 25 bolts. The average length in the sample was 15.95 inches with a variance of 0.4 inches. The acceptable variance for the length is 0.3 inches. (Note that 1 inch is equivalent to 2.54 cm). a. Construct a 95% confidence interval for the population variance. b. State the null and alternative hypotheses to test whether or not the population variance equals 0.3 inches. c. Compute the test statistic.

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