Asix-lane freeway (three lanes in each direction) with a 5.5% uphill grade 1.5 miles long has 10-ft lanes and obstructions 5 ft from the right edge. there are zero ramps within three miles upstream of the segment midpoint and one ramp within three miles downstream of the segment midpoint. the traffic stream has a peak hour factor of 0.84, peak-hour volume of 2500 vehicles with 3% rvs, 2% other single unit trucks, and 5% tractor trailer trucks. what is the level of service?

a. los a
b. los b
c. los c
d. los d