How to find Basic earnings per share and Diluted earnings per share with the given the following year-end information?

• Net income, $15,000
• The income tax rate, 30%
• 4,000 shares of common stock were outstanding the entire year.
• 500 shares of 10%, $50 par (and issuance price) convertible preferred stock were outstanding the entire year. Dividends of $2,500 were declared on this stock during the year. Each share of preferred stock is convertible into 5 shares of common stock.