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The Tassel Ltd. has been presented with an investment opportunity which will yield end of year revenue of $20,000 per year in Years 1 through 4, $25,000 per year in Years 5 through 9, and $30,000 in YearlO. This investment will cost the firm $150,000 today, and the firm's required rate of return is 10 per cent. What is the NPV for this investment, if ignoring tax effect and depreciations? (20')