In Year 1 , Smith, a divorced person, provided over one half the support for his widowed mother, Ruth, and his son, Clay, both of whom are U. S. citizens. During Year 1 , Ruth did not live with Smith. She received $9, 000 in Social Security benefits. Clay, a 25-year-old full-time graduate student, and his wife lived with Smith. Clay had no income but filed a joint return for Year 1 , owing an additional $500 in taxes on his wife's income. How many exemptions was Smith entitled to claim on his Year 1 tax return? Justify all your answers