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O ooo O Carson Inc.'s manager believes that economic conditions during the next year will be strong, normal, or weak, and she thinks that the firm's returns will have the probability distribution shown below. What's the standard deviation of the estimated returns? (Hint: Use the formula for the standard deviation of a population not a sample.) Do not round your intermediate calculations. Economic Conditions Prob. Return Strong 304 37.04 Normal 40% 15.0% Weak 30 -18.0W O 15.10 12/408 0270 O d. 22.01 02147