please help me with these im lost

Dog Up! Franks is looking at a new sausage system with an installed cost of $685,000. This cost will be depreciated straight-line to zero over the project's 5 -year life, at the end of which the sausage system can be scrapped for $91,000. The sausage system will save the firm $195,000 per year in pretax operating costs, and the system requires an initial investment in net working capital of $47,000. If the tax rate is 21 percent and the discount rate is 10 percent, what is the NPV of this project? Note: Do not round intermediate calculations and round your answer to 2 decimal places, e.g., 32.16 . Consider a three-year project with the following information: Initial fixed asset investment =$705,000; straight-line depreciation to zero over the 5-year life; zero salvage value; price =$39.31; variable costs =$28.25; fixed costs =$329,000; quantity sold =86,000 units; tax rate =23 percent. How sensitive is OCF to changes in quantity sold? Note: Do not round intermediate calculations and round your answer to 2 decimal places, e.g., 32.16