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-36 Multiple Support Agreements. Anna, age 65, who lives with her unmarried son, Mario, received $7,000, which was used for her support during the year. The sources of support were as follows: Social Security benefits $1,500 Mario 2,600 Caroline, an unrelated friend 800 Doug, Anna's son 500 Elaine, Anna's sister 1,600 Total $7,000 The Social Security benefits are wholly tax-exempt in this situation. Assume a multiple support agreement (Form 2120) is properly filed. a. Who is eligible to claim Anna as a qualifying relative? b. If Mario wants to claim Anna as a qualifying relative, who must agree to it? c. If Mario claims Anna as a qualifying relative, what is his standard deduction