18. 4.00 points The Short-Line Railroad is considering a $180,000 investment in either of two companies. The cash flows are as follows: $ 80,000 50,000 50,000 4-10 20,000 S 30,000 70,000 80,000 20,000 a. Compute the payback period for both companies. (Round your answers to 1 decimal place.) Electric Co. Waner Works 3.0 years 3 years b. Which of the investments is superior from the information provided? Water Works OElectric Co 2 3 4