Regent Industries is considering a new capital budgeting project that will last for three years. Regent plans on using a cost of capital of $12\%$ to evaluate this project. Based on extensive research, it has prepared the following incremental cash flow projections:

$\backslash$table$[[$Year$,0,1,2,3],[$Sales $($Revenues$),,100,000,100,000,100,000],[-$ Cost of Goods Sold,,$50,000,50,000,50,000],[-$ Depreciation,,$30,000,30,000,30,000],[=$ EBIT,,$20,000,20,000,20,000],[-$ Taxes $(35\%),,7000,7000,7000],[=$ unlevered net income,,$13,000,13,000,13,000],[+$ Depreciation,,$30,000,30,000,30,000],[+$ changes to working capital,,$-4500,-4500,9,000],[-$ capital expenditures,$90,000,,,]]$

$(1)$ What is the NPV of this project?

$(2)$ Regent is worried about the reliability of the sales forecast. How sensitive is the project's NPV to a $10\%$ change in sales? $($Assuming sales affects COGS but doesn't affect NWC$)$

$(3)$ How sensitive is the project's NPV to a $10\%$ change in COGS?