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The market value balance sheet of Southern Cement shows that common stock is valued at $70 million and debt is valued at $30 million. Investors currently require a 15% return on the common stock and a 4% return on the debt. If Southern Cement issues an additional $20 million of common stock and uses this money to retire debt, find the new required rate of return on the stock. Assume that the change in capital. structure does not affect the interest rate on Southern Cement's debt and that there are no taxes. (10 marks)