User support managers often use which of these strategies to determine how many staff members to hire to handle the volume of support incidents received

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?