Thanks to an investment of $ 800,000, A-Design Inc., a company specializing in the design and management of armrests, was able to generate an operating profit of $ 36,000 in the first year of its existence. Her first year interest was $ 5,000. 1. Calculate the net profit of the corporation for a tax rate of 25%. 2. Determine the return on the company's invested capital. 3. What is the period of the simple return on investment of A-Design Inc.? 4. For a unit price of $ 50 armrests, how many armrests should A-Design sell to break even? 5. Make a sensitivity analysis of A-Design's net profit for a tax rate of 20% and 30%.