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Ian retired in June 2019 at the age of 71. Ians retirement account was valued at $490,000 at the end of 2018 and $500,000 at the end of 2019. He has had all of his retirement accounts open for 15 years. What is Ians required minimum distribution for 2020 under each of the following alternative scenarios? (Leave no answer blank. Enter zero if applicable.) (Use Exhibit 13-3) Ian's retirement account is a traditional 401(k) account. Ian's retirement account is a Roth 401(k) account. Ian's retirement account is a traditional IRA. Ian's retirement account is a Roth IRA.