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2. An individual surrenders, for $20,000, an endowment life insurance policy in which he had a $15,000 investment. How much of the $20,000 of proceeds must be included in gross income? 3. What effect does interest on tax-exempt bonds have on the taxation of social security benefits? 4. How is the amount of Social Security benefits included in taxable income calculated? 5. On Series EE U.S. savings bonds, what different tax consequences arise from the two choices in reporting interest? 6. List several social justifications for issuing private activity bonds