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Beckham Corporation has 3,000 shares of $100 par value, 7% cumulative preferred stock, and 10,000 shares of $10 par value common stock outstanding during its first five years of operation. Beckham Corporation paid cash dividends as follows: 2018, $30,000; 2019, s0: 2020, $65,000; 2021, $30,000; 2022, during $15,000. The amount of dividends received by the common stockholders 2021 was: Select one: a. $30,000 b. $21,000 C. $9,000 d. $0