nformation on four investment proposals is given below: investment proposal a b c d investment required $ (60,000) $ (190,000) $ (110,000) $ (2,660,000) present value of cash inflows 88,600 260,600 168,600 3,551,000 net present value $ 28,600 $ 70,600 $ 58,600 $ 891,000 life of the project 5 years 7 years 6 years 6 years required: 1. compute the profitability index for each investment proposal. (round your answers to 2 decimal places.) 2. rank the proposals in terms of preference.