Darrien Nominees is seeking to raise new finance and needs to know its existing WACC. It can comfortably raise debt capital at an after-tax cost of 6.7% and its costs of equity were 9.2% for preference shares and 10.6% for ordinary shares. The firms percentages of debt, preference shares and ordinary shares were allocated as; 55%, 30% and 15% based on book values, and 55%, 10% and 35% based on market values. What is the firms approximate WACC?