Question: An investor is trying to decide whether to invest in a given stock, but is worried about the volatility of the investment. If the investor is very certain that the volatility (as measured by the standard deviation) is greater than 15% then the investor will choose a different investment option. In a sample of the previous 101 days reveals that the standard deviation of the investment is 20%. At the 1% level of significance, does it appear that the standard deviation of grades is higher than 15% (or variance is greater than 225)?