67. Ken is 63 years old and unmarried. He retired at age 55 when he sold his business, Understock.com. Though Ken is retired, he is still very active. Ken reported the following financial information this year. Assume Kens modified adjusted gross income for purposes of the bond interest exclusion and for determining the taxability of his Social Security benefits is $70,000 and that Ken files as a single taxpayer. Determine Kens 2009 gross income. d. Ken received $13,000 in Social Security benefits for the year