A rural freeway has an ideal free-flow speed of 120 km/h and two 3.6 m lanes in each direction, with right shoulder lateral clearance of 1.2 m. Interchanges are spaced approximately 5 km apart. Traffic consists of 10 percent trucks and buses and 8 percent recreational vehicles. The adjustment for driver population factor is estimated to be 0.80.
a. If the maximum 15-min flow rate is 1,760 veh/h, what is the level of service on a 1.7 km long 3.1 percent upgrade?
b. If the generalized terrain for the freeway described as rolling terrain, How many lanes are required to provide level of service B?