Auto Parts Inc is considering two expansion projects, Project C and Project D. The cash flows are as follows:

Year	Project C	Project D
0	$(100)	$(120)
1	40	50
2	50	60
3	60	70
4	70	80

The required rate of return is 15%. Analyze and determine:

a. The payback period for each project. b. The NPV for each project. c. The IRR for each project. d. Which project has the higher NPV? e. Discuss the strategic importance of each project for the company's growth.