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3. (10 Percent) A firm's products are sold for $80 each. The fixed costs (non-depreciation) are $1,000 per year, and the variable costs per unit are 70% of the selling price. The initial investment of $3,000 will be depreciated straight-line over its useful life of six years to a final value of zero, and the discount rate is 10%. The firm's tax rate is 30%. Calculate the NPV break-even level of sales