An office equipment manufacturer has developed a new photocopy machine and would like to estimate the average number of 81/2-by-11 copies that can be made using a single bottle of toner. For a simple random sample of 20 bottles of toner, the average was 1535 pages, with a standard deviation of 30 pages. Making and stating whatever assumptions you believe are necessary, construct and interpret the 95% confidence interval for the population mean.