a) Suppose you are trying to estimate the population mean for quarterly net income at your company.You have sampled 53 months and you calculated the average net income to be $900 million, with a standard deviation of $62 million.Note that this standard deviation is of raw data.Your company has been in business for 50 years (quite a long time, think how many months that is!).Please calculate a confidence interval for your sample mean, assuming you wish to be 92% confident.Hint:Consider the use of FPCF?Maybe not, but consider.

b) Use the information in part a, but now you have sampled only 20 months.Assume your standard deviation is of sample mean data.Be 80% confident in your confidence interval calculation.Hint:FPCF used here?