Using the data in the following table, and the fact that the correlation of A and B is 0.33, calculate the volatility (standard deviation) of a portfolio that is 50% invested in stock A and 50% invested in stock B. (Click on the following icon in order to copy its contents into a spreadsheet.) Year 2008 2009 2010 2011 2012 2013 Realized Returns Stock A Stock B - 12% 27% 15% 24% 2% 3% - 8% -7% 3% - 4% 14% 26% The standard deviation of the portfolio is %. (Round to two decimal places.)