Integrative$-$Optimal capital structure Medallion Cooling Systems, has total assets of $$9,000,000,$ EBIT of $$1,980,000,$ and preferred dividends of $$205,000$ and is taxed at a rate of $40\%.$ In effort to determine the optimal capital structure, the firm has assembled data on the cost of debt, the number of shares of common stock for various levels of indebtedness, and the overall requir return on investment:

$\backslash$table$[[\backslash$table$[[$Capital structure$],[$debt ratio$]],$Cost of debt, $r_d,\backslash$table$[[$Number of common$],[$stock shares$]],$Required return, $r_s$