Evan has a portfolio with two stocks. He invested 50% into stock A with a standard deviation of 16%, and the remaining into stock B with a standard deviation of 17%. The correlation between the two stocks is 0.17. What is the standard deviation of Evans portfolio? (Round your answer as decimals with four decimal places, such as 0.1234. For example, if your answer is 12.34%, write 0.1234. DO NOT write your answer as percentages as you will be marked wrong.)