Determine the IRR on the following projects

Determine the IRR on the following projects

a. Initial outlay of $35,000 with an after-tax cash flow at the end of the year of $5,836 for seven years

b. Initial outlay of $350,000 with an after-tax cash flow at the end of the year of $70,000 for seven years

c. Initial outlay of $3,500 with an after-tax cash flow at the end of the year of $1,500 for three years