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Use the following information on states of the economy and stock returns to calculate the standard deviation of returns. (Do not round intermediate calculations. Enter your answer as a percent rounded to 2 decimal places.) Probability Security of Return State of if State State of Economy Economy occurs Recession 15 -6.50% Normal . 20 10.00 Boom . 65 20.00 * Answer is complete but not entirely correct. Standard deviation 9.63 x 9%