How do I begin to do the following scenario?

You work for an investment banking firm and have been asked by management of Vestor Corporation (not real), a software development company, to calculate its weighted average cost of capital, to use in evaluating a new company investment. The firm is considering a new investment in a warehousing facility, which it believes will generate an internal rate of return of 11.5%. The market value of Vestor's capital structure is as follows:

Source of Capital	Market Value
Bonds	$10,000,000
Preferred Stock	$2,000,000
Common Stock	$8,000,000

To finance the investment, Vestor has issued 20 year bonds with a $1,000 par value, 6% coupon rate and at a market price of $950. Preferred stock paying a $2.50 annual dividend was sold for $25 per share. Common stock of Vestor is currently selling for $50 per share and has a Beta of 1.2. The firm's tax rate is 34%. The expected market return of the S&P 500 is 13% and the 10-Year Treasury note is currently yielding 3.5%.