The file Dow Jones contains date, open, high, low, close, and volume for the Dow Jones Industrial Average (DJIA) for almost eight years of trading days.

a. Assuming that the data in the file constitute the population of interest, what is the population mean closing value for the DJIA?

b. Using Excel, select a random sample of 10 days’

closing values (make certain not to include duplicate days) and calculate the sample mean and the sampling error for the sample.

c. Repeat part b with a sample size of 50 days’ closing values.

d. Repeat part b with a sample size of 100 days’

closing values.

e. Write a short statement describing your results.

Were they as expected? Explain.