please, it's the third time that I am asking for help with this question bc the tutors gave me the wrong answers. so it's the last attempt that I have. I need help with it .

thank you so much .

Help Using the data in the following table, and the fact that the correlation of A and B is 0.56, calculate the volatility (standard deviation) of a portfolio that is 50% invested in stock A and 50% invested in stock 8. 21% Year 2008 2009 2010 2011 2012 2013 Realized Returns Stock A Stock B -2% 11% 22% 2% 15% - 6% - 2% 2% - 6% 6% 30% The standard deviation of the portfolio is %. (Round to two decimal places.)