cori's dog house is considering the installation of a new computerized pressure cooker for hot dogs. the cooker will increase sales by $8,100 per year and will cut annual operating costs by $12,600. the system will cost $44,100 to purchase and install. this system is expected to have a 4year life and will be depreciated to zero using straight line depreciation and have no salvage value. the tax rate is 21 percent and the required return is 10.1 percent. what is the NPV of purchasing the pressure cooker ?