Asample containing years to maturity and yield for 40 corporate bonds are 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.

Economic models a. are constructed to mirror reality as closely as possible, and in this respect economic models are no different from other scientific models. b. are constructed to mirror reality as closely as possible, and in this respect economic models are very different from other scientific models. c. are simplifications of reality, and in this respect economic models are no different from other scientific models. d. are simplifications of reality, and in this respect economic models are very different from other scientific models.