Please utilise the following key economic and financial data for the firm Sour Plum Co. The firm has an interest rate on debt of 5.0% and the cost of equity capital is 15.0%. The market value and book value of debt are approximately equal. The company has earnings before interest and tax (EBIT) of $180.0 million, debt of $400.0 million, market value of equity of $800.0 million and book value of equity of $100.0 million. The Sales are $400.0 million and the tax rate is 30%. Comparable firms have average interest coverage of 3.0x and average debt-to-equity ratios of 1.0x on a market value basis. They also have average EBIT/Sales ratios of 26.7%. This firm has half the proportion of variable costs to sales, versus the comparable firms. The comparables have a variable costs to sales ratio of 20.0%.

What is ROE?