Using continous compounding rate of 5%, what is the present value of $100 you are to receive in 3 years? g

Here are the expected cash flows for three projects: cash flows (dollars) project year: 0 1 2 3 4 a − 6,100 + 1,275 + 1,275 + 3,550 0 b − 2,100 0 + 2,100 + 2,550 + 3,550 c − 6,100 + 1,275 + 1,275 + 3,550 + 5,550 a. what is the payback period on each of the projects? b. if you use a cutoff period of 2 years, which projects would you accept?