A Class I two-lane highway is on level terrain, has a measured free-flow speed of 65 mi/h, and has 50% no-passing zones.
During the peak hour, the analysis direction flow rate is 182 veh/h, the opposing direction flow rate is 78 veh/h, and the PHF = 0.90. There are 15% large trucks and buses (no RVs). Determine the level of service.