In each of the following cases, determine the amount incudible in David's gross estate:
a. An account balance of $200,000 in an IRA that the beneficiary immediately withdrew.
b. A commercial annuity with a present value of $60,000, payable to David's wife, Selma, who contributed 40 percent of the purchase price.
c. A qualified pension annuity with a present value of $180,000, one-third of which is attributable to David's own contributions, payble to Selma.
d. A lump-sum distribution from a qualified profit-sharing plan of $30,000 payable to David's son, Kyle, who used five-year averaging.