(Use Excel) An investor wants to test whether the average return of Vanguard's Precious Metals and Mining Fund is greater than 12% based on data over the past 25 years. Assume returns are normally distributed with a population standard deviation of 30%.

a. State the null and the alternative hypotheses for the test.

b. Open the Metals data from the text website into an Excel spreadsheet. Use the function Z.TEST to calculate the p-value.

c. At α = 0.05 what is the statistical conclusion?

d. Is the return on Vanguard's Precious Metals and Mining Fund greater than 12%? P-56