A stock will have a loss of 13.8 percent in a recession, a return of 12.5 percent in a normal economy, and a return of 27.2 percent in a boom. There is 31 percent probability of a recession, 34 percent probability of normal economy, and 35 percent probability of boom. What is the standard deviation of the stock's returns? rev: 05_04_2018_QC_CS-126555 28.10% 16.76% 14.37% 15.37% 12.57%