what did i do wrong. please use financail calculator to do this question

P14-16 PROBLEM 14-16 Net Present Value Analysis LO14-2 Windhoek Mines, Ltd., of Namibia, is contemplating the purchase of equipment to exploit a mineral deposit on land to which the company has mineral rights. An engineering and cost analysis has been made, and it is expected that the following cash flows would be associated with opening and operating a mine in the area: "Recelpts from sales of ore, less out-of-pocket costs for salarles, utilities, insurance, and so forth. The mineral deposit would be exhausted after four years of mining. At that point, the working capital would be released for reinvestment elsewhere. The company's required rate of return is 20% (1) pmt=120000