According to the bar graph when did scientist begin taking measurements of the dead zone

You inherit $500,000 from your parents and want to use the money to supplement your retirement. you receive the money on your 65th birthday, the day you retire. you want to withdraw equal amounts at the end of each of the next 25 years. what constant amount can you withdraw each year and have nothing remaining at the end of 25 years if you are earning 6% interest per year? a. $20,000 b. $28,489 c. $33,574 d. $39,113