Using the data in the following table, and the fact that the correlation of A and B is 0.48, calculate the volatility (standard deviation) of a portfolio that is 50% invested in stock A and 50% invested in stock B. 0 Year 2008 2009 2010 2011 2012 2013 Realized Returns Stock A Stock B - 13% 16% 16% 23% 10% 14% - 10% -3% 2% -7% 10% 18% The standard deviation of the portfolio is %. (Round to two decimal places.)