A certain medical device will result in an estimated $20,000 reduction in hospital labor expenses during its years of operation. Additional operating expenses for the device (maintenance, electric power, etc.) are $3,500 annually, and they increase by $250 per year thereafter (i.e., $3,750 in year two and so on). It is anticipated that the device will last for 10 years and will have no market value at that time. If the MARR is 10% per year calculate the PW of the project