Consider the following firm with a capital structure of 15% debt, 80% equity, and 5% preferred stock (all based on market values). The outstanding debt has a yield-to-maturity of 4%, whereas both regular equity and preferred equity are currently priced at $100. The regular annual dividends are expected to be $5 next year (t=1) growing at 2% annually. Preferred dividends are $4.75 (non-growing) per year. The firm pays 20% in taxes.

Based on this information, what is R_wacc for this firm, given a risk-free rate of return of 2% and an expected return on the market portfolio equal to 8%?