A contractor knows that he must replace a mobile crane in 9 years at an estimated cost of $550000. How much should he deposit today and at the beginning of each of the next 7 years (all equal payments) at an interest rate of 10% to have the needed $550000 at the end of the 9 years? What is the accumulated equivalent amount just after the last deposit? How much annual amount should be deposited as mentioned in the statement of the