Suppose you had held a portfolio consisting of 50% of Stock A and 50% of Stock B. What would have been the average return on the portfolio during this period? Year rA rB 2009 -30.00% -7.50% 2010 63.00% 22.50% 2011 30.00% -19.50% 2012 -12.00% 75.00% 2013 37.50% 18.00%