Suppose the City of Columbia is considering investing in motion sensor traffic lights that allow traffic lights to change automatically based on the travel patterns of cars. The upfront cost of the investment is $1,000,000 (i.e. cash outflow) while Columbia residents are willing to pay $200,000 annually (i.e. cash inflow) over the next ten years to fund this increase. Based on the ordinary payback period, the expected payback period is City of Columbia has a discount rate of 5%, using the discounted payback approach, the discounted payback period is If the City of Columbia's acceptable payback period is 5.5 years, we should the project under the ordinary payback and the project under the discounted payback period. (a) 6 years; 6 years; reject; reject (b) 5 years; 5.50 years; accept; accept (c) 5.90 years; 5 years; reject; accept (d) 5 years; 5.90 years; accept; reject