Final answer:
A Roth IRA is a retirement account that allows tax-free withdrawals during retirement. The 20-year retirement consumption stream will depend on the savings and investment returns.
Step-by-step explanation:
A Roth IRA is a retirement account that allows individuals to contribute after-tax income and withdraw the funds tax-free during retirement. When you choose to save in a Roth IRA for your retirement, you are essentially investing in stocks, bonds, or mutual funds with the goal of growing your retirement savings over time. The 20-year retirement consumption stream from a Roth IRA would depend on the amount you have saved and the investment returns earned during that period. The withdrawals from a Roth IRA can be customized based on your financial needs during retirement.