7) Consider the following returns: Year End 2004 2005 2006 2007 2008 2009 Stock X Realized Return 20.1% 72.7% -25.7% 56.9% 6.7% 17.9% Stock Y Realized Return -14.6% 4.3% -58.1% 71.1% 17.3% 0.9% Stock Z Realized Return 0.2% -3.2% -27.0% 27.9% -5.1% -11.3% a) The Volatility (standard deviation) on Stock Y's returns is closest to: A) 35% B) 31% 42%. D) 18%. b) The variance on a portfolio that is made up of equal investments in Stock X and Stock Z is closest to (Note: Standard deviation of stock X: 0.3542; Standard deviation of stock Z10.1796; Correlation Coefficient between stock X and Z: 0.715) A) 0.82. B) 0.05. 101201) 6.710 C) 0.12. D) 0.06