1. McTree Inc.'s manager thinks that economic conditions during the next year will be strong, normal, or weak, and he 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 calculations.

   Economic
   Conditions		Prob.		Return
   Strong		30%		40.0%
   Normal		40%		10.0%
   Weak		30%		-16.0%

   	a.	24.75%
   	b.	17.59%
   	c.	21.71%
   	d.	22.58%
   	e.	25.18%