How do you do longhand

(a) First identify the sample statistic n and the degrees of freedom.

(b) The confidence interval for the population standard deviation is can be found by taking the square roots of the left and right

endpoints of the confidence interval for the population variance.

Calculate the confidence interval for the population standard deviation, rounding to three decimal places.

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 J. Interpret the results. 4.472 4.431 4.012 4.331 4.002 3.775 3.814 3.747 4.216 3.967 4.114 4.526 3.972 3.759 3.866 3.828 4.462 (a) The confidence interval for the population variance is (].). (Round to three decimal places as needed.)