5. On September 16, 20X1, the executor for Paul Postmortem's estate filed Paul's estate tax return. On December 30, 20X2, the IRS assessed additional estate tax in the amount of $300,000. This assessment resulted from the IRS including in the gross estate a gift in the amount of $1,500,000 that was determined to be a transfer with a retained life estate. The additional estate tax resulting from the inclusion of the gift in the gross estate was actually $500,000, but the estate received credit under Code Sec. 2012 for the $200,000 of gift tax paid at the time of the filing of the gift tax return. The estate paid the $300,000 plus interest on January 2,203