PROBLEM D is a one$-$third general partner in the DEF partnership. Both D and the partnership are cash method, calendar year taxpayers. D dies at a time when the partnership has earned $$15,000$ for the current year, and his share of the untaxed and undistributed partnership income for the year is $$5,000.$ Under all of the sale or liquidation agreements described below, D is to be paid $$30,000$ for his interest, which includes his share of current$-$year income. At the time of D$\text{'}$s death, and before making any adjustments on account of the operating income generated during the current year, the DEF partnership has the following balance sheet: Assets Assume, alternatively, that D$\text{'}$s interest: $(1)$ passes to his estate; $(2)$ is subject to a buy$-$out agreement at his death; $(3)$ is liquidated by the partnership $($which is a services partnership$)$; or $(4)$ is liquidated by the partnership in which capital is a material income$-$producing factor. Under each alternative, consider the following questions: $($a$)$ Does the partnership's taxable year close as to D$\text{'}$s estate? $($b$)$ What is the amount included in D$\text{'}$s gross estate? $($c$)$ To what extent does the interest included in D$\text{'}$s gross estate constitute income in respect of a decedent? $($d$)$ what outside basis does D$\text{'}$s estate take in the partnership interest immediately following D$\text{'}$s death?