Redwood Corporation is considering two alternative investment proposals with the following data: Proposal X Proposal Y Investment $840,000 $486,000 Useful life 8 years 8 years Estimated annual net cash inflows for 8 years $140,000 $63,000 Residual value $52,000 $- Depreciation method Straight-line Straight-line Required rate of return 16% 9% How long is the payback period for Proposal X? O A. 7.71 years B. 16.15 years O c. 6 years OD. 13.33 years