The following information pertains to Mighty Corporation's outstanding stock for the year just ended. Common stock, $5 par value: Shares outstanding, 1/1 20,000 2-for-1 stock split, 4/1 20,000 Shares issued, 7/1 10,000 Preferred stock, $10 par value, 5% cumulative: Shares outstanding, 1/1 4,000 How many shares should Mighty use to calculate basic earnings per share? 45,000 40,000 54,000 50,000