Luther Inc., has 4,000 shares of 5%, $50 par value, cumulative preferred stock and 100,000 shares of $1 par value common stock outstanding at December 31, 2018, and December 31, 2017. The board of directors declared and paid an $8,000 dividend in 2017. In 2018, $40,000 of dividends are declared and paid. What are the dividends received by the preferred stockholders in 2018?