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The diameters (in inches) of 17 randomly selected bolts produced by a machine are listed. Use a 90% level of confidence to construct a confidence interval for (a) the population variance of and (b) the population standard deviation o. Interpret the results. 4.482 4.411 4.009 4.308 4.009 3.767 3.818 3.747 4.219 3.975 4.156 4.555 3.962 3.734 3.848 8 3.802 4.438The number of hours of reserve capacity of 10 randomly selected automotive batteries is shown to the right. 1.73 1.85 1.51 1.66 1.71 1.97 1.39 1.58 1.46 2.02 Assume the sample is taken from a normally distributed population. Construct 99% confidence intervals for (a) the population variance 62 and (b) the population standard deviation o.As part of a water quality survey, you test the water hardness in several randomly selected streams. The results are shown below. Construct a condence interval for the population variance 6'2 and the population standard deviation 6. Use a 90% level of condence. Assume that the population has a normal distribution. n = 13 s =13 grains per gallon What is the confidence interval for the population variance oz? [DD] (Round to one decimal place as needed.) The annual earnings of 13 randomly selected computer software engineers have a sample standard deviation of $3728. Assume the sample is from a normally distributed population. Construct a confidence interval for the population variance oz and the population standard deviation o. Use a 95% level of confidence. Interpret the results. What is the confidence interval for the population variance o2? ) (Round to the nearest integer as needed.)