Modern Artifacts can produce keepsakes that will be sold for $220 each. Nondepreciation fixed costs are $3,800 per year, and variable costs are $200 per unit. The initial investment of $10,000 will be depreciated straight-line over its useful life of five years to a final value of zero, and the discount rate is 10%. a. What is the accounting break-even level of sales if the firm pays no taxes? b. What is the NPV break-even level of sales if the firm pays no taxes? (Do not round intermediate calculations. Round your final answer to the nearest whole number.) c. What is the accounting break-even level of sales if the firm's tax rate is 20% ? d. What is the NPV break-even level of sales if the firm's tax rate is 20\%? (Do not round intermediate calculations. Round your final answer to the nearest whole number.) e. What is the degree of operating leverage for the firm for the NPV break-even points when the tax rate is 0% and when the tax rate is 20\%? (Round intermediate calculation to the nearest whole number. Round your answers to 2 decimal places.)