A nightclub, a cash basis taxpayer, desperately wanted to secure the singing services of Johnny Cash (also a cash basis taxpayer) for a December 20, 2021 performance. The nightclub offered Johnny $10,000 in cash payable immediately after his last song on the 20th. Johnny declined the offer saying, "I don't want to be paid this year for tax reasons." After several phone calls of negotiations, the parties later agreed Johnny would be given an unsecured, assignable promissory note for $10,000, payable on January 5, 2022. As planned, on December 20, 2021, Johnny Cash sang at the nightclub and received the unsecured promissory note. Assume the nightclub is a very wealthy corporation and the note's FMV is $10,000. On January 5, 2022, the nightclub paid Johnny $10,000 in cash.

1. How should the nightclub account for the expense of Johnny Cash’s performance in its financial statements for the year 2021?
2. What are the tax implications for Johnny Cash receiving a promissory note in December 2021 but getting paid in January 2022?
3. Is the issuance of an unsecured, assignable promissory note considered income for Johnny Cash in the year 2021 or 2022?
4. How does the fair market value (FMV) of the promissory note impact the recording of the transaction on the nightclub’s books?