Kirkus Corporation has 19,000 shares outstanding of $8 par value, 8% preferred stock, and 38,000 shares outstanding of $8 par-value common stock. In its first 5 years of operation, the company paid the following dividends: 2018, $0; 2019, $12,160; 2020, $36,480; 2021, $0; 2022, $68,440. Calculate the dividends paid to preferred and common stockholders under the following three independent situations:
a. Preferred stock is noncumulative and nonparticipating.
b. Preferred stock is cumulative and nonparticipating.
c. Preferred stock is cumulative and fully participating.