A portfolio is composed of two stocks, A and B. Stock A has an expected return of 24% and a standard deviation of return of 29%, while stock B has an expected return of 15% and a standard deviation of return of 18%. The correlation coefficient between the returns on A and B is .53. Stock A comprises 64% of the portfolio, while stock B comprises 36% of the portfolio. What is the standard deviation of the return on this portfolio?