Year Investment Operating income M$ Net cash Flow Cum net cash flow M$ 0 M$ -30 30 M$ -30 1 50 70 -20 -50 2 150 500 -350 3 340 -400 -60 340 4 430 430 520 370 5 520 890 Sum You have a working interest in a lease with the operating income and investment profile above. a) Between which years does the payback period take place? b) What is the maximum exposure and when does it occur? c) What the undiscounted return on investment (ROI) for this project? d) What is the undiscounted profit to investment ratio where profit = net cash flow