Consider the following returns and states of the economy for Neptune Corporation: Economy Probability Return Weak 15% -5% Normal 50% 2% Strong 35% 6% What is the standard deviation of the firm's returns? SET YOUR CALCULATOR TO FOUR DECIMAL PLACES AND ROUND TO 2 DECIMAL PLACES AT THE END. DO NOT ENTER THE %. FOR EXAMPLE, IF YOUR ANSWER IS 7.7011% ENTER ITAS 7.70