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The performance of the common stock of Apple Stores is highly dependent upon the state of the economy. In a boom economy, the stock is expected to return 22.0% in comparison to 13.0% in a normal economy and negative 11.0% in a recessionary period. The probability of a recession is 14%. There is a 28% chance of a boom economy. The remainder of the time the economy will be at normal levels. What is the standard deviation of the returns on Apple stock? Multiple Choice 4.96% 10.13% 18.23% 10.74% 12.66%