As the winner of the Friendly Lottery, you are entitled to one of the following prizes:

a) $80,000 per year forever (the first payment starting next year).

b) $144,000 per year for the next 10 years starting immediately.

c) $320,000 payable every 2 years over 20 years.

d) $20,000 starting next year growing by 5.5% forever. Which prize will provide you a higher present value if r = 7%?