11.Data taken over a long period of time have established that the standard deviation of percentage iron in an iron analysis is 0.12, and that is not expected to change. A representative, well-mixed...

11.Data taken over a long period of time have established that the standard deviation of percentage iron in an iron analysis is 0.12, and that is not expected to change. A representative, well-mixed ore sample is analyzed six times, so the sample size is 6. If the true iron content is 32.60 percent
iron, if there is no systematic error, and if the normal distribution applies, what is the 95%
confidence interval for sample means?
To answer this question, what is µ?
A. 0.12 B. 32.60% C. 6 D. 5%

12.In Problem 11, what is the level of significance of the test?
A. 95% B. 5% C. 2.5% D. 97.5%

13.In problem 11, what test statistic do you need to solve for?
A. Z-statistic C. Chi-squared value
B. T-statistic D. F- statistic