Tippy Toe Spa Company offers various services, such as facials, laser hair removal and microdermabrasion. Currently, the company is considering purchasing the following spa equipment: Assume that each equipment's annual cash flow will occur for the penod equal to its useful life. Do not enter dollar signs or commas in the input boxes. Use the present values tables in the textbook appendix, Use the negative sign for negative values. Round your answers to the nearest whole number. a) Determine the NPV of each piece of equipment