I can't seem to find parts b and c... I need help!

Suppose Wesley Publishing's stock has a volatility of 50%, while Addison Printing's stock has a volatility of 30%. If the correlation between these stocks is 60%, what is the volatility of the following portfolios of Addison and Wesley: a. 100% Addison b. 75% Addison and 25% Wesley c. 50% Addison and 50% Wesley a. The volatility of a portfolio of 100% Addison stock is 30 %. (Round to two decimal places.) b. The volatility of a portfolio of 75% Addison and 25% Wesley is | %. (Round to two decimal places.)