Researchers plan to estimate the average daily output for the 2300 firms in the metal fabricating industry. You randomly select 60 of the firms and find that the average daily output for firms in the sample is 1560 units, with a sample standard deviation of 320 units.
a. Construct a 99% confidence interval estimate of aver-age daily output per firm for all industry firms.
b. Estimate, at the 99% confidence level, the total combined daily output for the industry as a whole.