Suppose that a randomly chosen stock has on average a standard deviation of 0.28 and a beta of 1. The market portfolio has a standard deviation of 0.20.

If the single index model is correct, what is your estimate of the standard deviation of an equally-weighted portfolio of five (5) randomly chosen stocks?

Enter your answer in raw decimal form to four (4) decimal places. For example, "6.149%" should be entered as "0.0615".