North Around, Inc. stock is expected to return 22 percent in a boom, 13 percent in a normal economy, and -15 percent (negative 15%) in a recession. The probabilities of a boom, normal economy, and a recession are 6 percent, 92 percent, and 2 percent, respectively. What is the standard deviation of the returns on this stock? A) 20.54 percent B) 4.6 percent C) 2.15 percent D) 18.79 percent OE) 4.53 percent