Summary statistics for returns on two stocks X and Y are listed below. The covariance of returns on stocks X and Y is Q.002700. Consider a portfolo of 60% stock X and 40% stock Y What is the standard deviation of portfolio returns? Please specily your answer in decimal terms and round your answer to the nearest thousandth (e.g.) enter 12.3 percent as 0.123 ). Note that the correct answer will be evaluated based on the full-precision result you would obtain using Exal