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 54% probability that the firms will have a 7% return and a 46% probability that the firms will have a - 7% return. Plot the volatility as a function of the number of firms in the two portfolios. The standard deviation of type S stock is %. (Round to two decimal places.)