X 5.3.9 Find the final amount in the following retirement account, in which the rate of return on the account and the regular contribution change over time. $519 per month invested at 5%, compounded monthly, for 4 years, then $793 per month invested at 7%, compounded monthly, for 4 years. What is the amount in the account after 8 years? (Do not round until the final answer. Then round to the nearest dollar as needed.)