4. Proposals L and K each cost $500,000, have 6-year lives, and have expected total cash flows of $720,000. Proposal L is expected to provide equal annual net cash flows of S120,000, while the net cash flows for Proposal K are as follows: Year 1 $250,000 Year 2 200,000 Year 3 100,000 Year 4 90,000 Year 560,000 Year 6 20,000 $720,000 Determine the cash payback period for each proposal