Client is a non-eligible designated beneficiary who inherited his mother’s IRA in 2022. His mom was 80 when she died and she had been taking her RMD’s all along. He has not taken any distributions since inheriting the account (taking advantage of IRS penalty waiver for RMD’s not taken through 2024) and now needs to take distribution in 2025 (assuming IRS does not grant penalty relief in 2025). How does he calculate his RMD for 2025?