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n A demand loan of $8000 is repaid by payments of $3000 after fifteen months, $4000 after thirty months, and a final payment after four years. If interest was 8% for the first two years and 9% for the remaining time, and compounding is quarterly, what is the size of the final payment? The size of the final payment is $ (Round the final answer to the nearest cent as needed. Round all intermediate values to six decimal places as needed.)