A company is considering the purchase of a new machine that will last eight years and cost $90,000 in the first year, decreasing by $1,000 each year to $2,000 in the eighth year. Determine how much money should the company set aside to pay for this machine:

a. If the interest rate is 4 percent per year, compounded annually.

b. If the interest rate is 7 percent per year, compounded annually.