A sample containing years to maturity and yield for 40

A sample containing years to maturity and yield for 40 corporate bonds is contained in the data file named CorporateBonds (Barron’s, April 2, 2012).,a. What is the sample mean years to maturity for corporate bonds and what is the sample standard deviation?,b. Develop a 95% confidence interval for the population mean years to maturity.,c. What is the sample mean yield on corporate bonds and what is the sample standard deviation?,d. Develop a 95% confidence interval for the population mean yield on corporate bonds.