The common stock of Escapist Films sells for $38 a share and offers the following payoffs next year: Calculate the expected return and standard deviation of Escapist. (Do not round your intermediate calculations and round your final answers to 2 decimal places. Use the minus sign for negative numbers if it is necessary.) The common stock of Leaning Tower of Pita, Inc., a restaurant chain, will generate the following payoffs to investors next year: The stock is selling today for $92. Calculate the expected return and standard deviation of a portfolio half invested in Escapist and half in Leaning Tower of Pita. (Do not round your intermediate calculations and round your final answers to 2 decimal places. Use the minus sign for negative numbers if it is necessary.) Why is the portfolio standard deviation lower than for either stock's individually? The portfolio standard deviation is lower than for either stock's individually because