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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 formals for the standard deviation of a population, not a sample.) Do not round your intermediate calculations. Economic Conditions Prob Return Strong 30% 40.0% Normal 409 10.09 Weak 30% 116.04 317594 2016 DS