4. [5 Points] The following table shows the historical returns and standard deviation of U.S. securities from 1926 to 2016: Securities Average Return Standard Deviation 12.0% 19.9% 16.6% 31.9% Large-company stocks Small-company stocks Long-term corporate bonds Long-term government bonds U.S. Treasury bills 6.3% 8.4% 6.0% 9.9% 3.4% 3.1% Which security has highest risk and why? How much is the average risk premium of large- company stocks