What is the standard deviation of the returns on a portfolio that is invested 45 percent in stock A and 55 percent in Stock B? State of Economy Probability of Returns if State Occurs State of Stock A Stock B Economy 10% 14% 16% Boom Normal 90% 8% 11% 2.47 percent 1.64 percent 2.63 percent 3.28 percent 3.41 percent