Required information [The following information applies to the questions displayed below.] Wendell's Donut Shoppe is investigating the purchase of a new $18,600 donut-making machine. The new machine would permit the company to reduce the amount of parttime help needed, at a cost savings of $3,800 per year. In addition, the new machine would allow the company to produce one new style of donut, resulting in the sale of 1,000 dozen more donuts each year. The company realizes a contribution margin of $1.20 per dozen donuts sold. The new machine would have a six-year useful life. (Ignore income taxes.) Requirement 2: Using Excel, calculate the internal rate of return promised by the new machine. (Round your answer to two decimal places. Omit the "\%" sign in your response.) Requirement 3: In addition to the data given previously, assume that the machine will have a $4,125 salvage value at the end of six years. Under these conditions, compute the internal rate of return. (Round your answer to two decimal places. Omit the "\%" sign in your response.)