a mining company will operate at a site for 10 years. at that time, regulators require them to restore the site to its original condition.

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a mining company will operate at a site for 10 years. at that time, regulators require them to restore the site to its original condition. to do this now would cost $15 million, but this cost is expected to rise by 7% per year. They are required to contribute to a fund an equal annual amount to build up the funds to do the restoration in year 10. These funds will be invested in bonds that yield 5.5%. how much must the mining company put in each year?