a. To find the federal income tax bill for the year, we multiply the taxable income by the federal tax rate:
Tax bill = $40,000,000 * 0.21 = $8,400,000.
b. If the firm receives an additional $4 million of interest income, the tax on this interest income would be the product of the interest income and the federal tax rate:
Tax on interest income = $4,000,000 * 0.21 = $840,000.
c. When 50% of dividends received are tax exempt, we find the taxable amount of dividends by multiplying the dividend income by 0.5 and then apply the federal tax rate to this amount:
Taxable dividend income = $4,000,000 * 0.5 = $2,000,000.
Tax on dividend income = $2,000,000 * 0.21 = $420,000.