Williams & Sons Enterprises borrows $10,000,000 at 7% c.a. interest payable yearly, the full principal due and payable in 20 years. To discharge the debt on its due date a sinking fund is established with annual deposits made estimated to earn 5% c.a. After 7 years has passed it's found that the sinking fund contains $2,300,000. Find the annual deposits necessary for the remaining 13 years if the estimated rate of interest is 4% c.a. [6]