You will need $100,000 per year for 25 years starting in year 45. You are able to save $3000 per year from year 3 to year 15, inclusive. How much must you save from years 16 through 37, inclusive, if interest rates will be 4% from years 0 through the end of year 25 and 7% starting at the beginning of year 26 and on? Solve for the unknown payments:

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