Expected Return, Variance, Std. Deviation and Cofficient of Variation: Magee 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?

State of the Economy	Probability of State Occurring	Stock's Expected Return
Boom	30%	26.10%
Normal	50%	16.05%
Recession	20%	14.10%
	15.67% 9.97% 14.96% 12.11% 14.25%