Springfield mogul montgomery burns, age 80, wants to retire at age 100 so he can steal candy from babies full time. once mr. burns retires, he wants to withdraw $500 million at the beginning of each year for 10 years from a special off-shore account that will pay 18% annually. in order to fund his retirement, mr. burns will make 20 equal end-of-the-year deposits in this same special account that will pay 18% annually. how large of an annual deposit must be made to fund mr. burns retirement plans?