What do you think is the reason for the 70 percent corporate-dividend exclusion?

ST1. During the past year, Alcore Enterprises, Inc., had sales of $3 million, cost of goods sold of $1.8 million, operating expenses of $800,000, and interest expenses of $200,000. Alcore paid preferred stock dividends of $100,000 and common stock dividends of $200,000 during the year. Alcore also retired maturing debt totaling $1.5 million during the year. Using the U.S. federal corporate tax rates shown in Table 2A.1, what was Alcore’s taxable income and its total tax liability for the year? What are Alcore’s average and marginal tax rates?
ST2. Jenkins Product, Inc., had sales of $5 million, cost of goods sold of $3 million, other operating expenses of $1 million, and interest expenses of $200,000 last year. During the year, Jenkins sold a plant and its associated equipment for $1.2 million. The book value of the plant and equipment was $500,000. What is Jenkins’s taxable income and what taxes are due? V=96