16-10 The state may eliminate a railroad grade crossing E by building an overpass. The new structure, together with the needed land, would cost $4 million. The analysis period is assumed to be 30 years because either the railroad or the highway above it will be relocated by then. Salvage value of the bridge (actu- ally, the net value of the land on either side of the railroad tracks) 30 years hence is estimated to be $750,000. A 5% interest rate is to be used. About 1000 vehicles per day are delayed by trains at the grade crossing. Trucks represent 30%. and 70% are other vehicles. Time for truck drivers is valued at $25 per hour and for other drivers at $7.50 per hour. Average time saving per vehicle will be 2 minutes if the overpass is built. No time saving occurs for the railroad. The railroad spends $75,000 annually for crossing guards. During the preceding 10-year period, the railroad has paid out $1.0 million in set- tling lawsuits and accident cases related to the grade crossing. The proposed project will entirely elimi- nate both these expenses. The state estimates that the new overpass will save it about 58000 per year in expenses directly due to the accidents. The overpass. if built, will belong to the state. Should the overpass be built? If the overpass is built, how much should the railroad be asked te contribute to the state as its share of the $4 million constriction cost