7. Philip began his professional corporation single practitioner CPA firm 38 years ago at age 27. He worked profitably as a sole practitioner for the full 38 years and is now age 63 and 2 months. He retired December 31, 2017. On January 1, 2018, he sold his practice for $400,000 to be received in four equal annual installments beginning on January 1, 2018. Is Philip eligible for Social Security retirement benefits during 2018? Why or why not