Consider an economy with two types of firms, S and I. S firms all move together. I firms move independently. For both types of firms there is a 42%probability that the firm will have a 22% return and a 58% probability that the firm will have a 18% return. What is the volatility (standard deviation) of a portfolio that consists of an equal investment in:

a.25 firms of type S?

b.25 firms of type I?

a. What is the volatility (standard deviation) of a portfolio that consists of an equal investment in 25 firms of type S? Standard deviation is ______%.

(Round to two decimal places.)