8. Calculate the internal rate of return on the following projects:

a. Initial outlay of $50,000 with an after-tax cash flow of $10,000 per year for eight years.

b. Initial outlay of $600,000 with an after-tax cash flow of $120,000 per year for ten years.

c. Initial outlay of $25,000 with an after-tax cash flow $11,500 per year for three years.