3. Drivers must slow from 70 mph to 40 mph to negotiate a severe curve on a rural highway. A warning sign for the curve is visible for 100 ft. How far in advance of the curve is it necessary to post the sign to insure that vehicles are able to properly decelerate? Assume f-0.30, G=0.0% and perception reaction time is 2 sec.

A driver will exit from a major road to enter a minor road via a ramp. From a distance of d1, he sees the EXIT sign located at d2 m before the exit RAMP (designed as a circular curve). He has to slow down to enter the RAMP safely while moving over the distance of (d1 + d2) on a 2-percent downgrade. He can read a road sign at a distance of 15 m for each 30 mm of the letter height. He will move along the ramp on a 3% downgrade and come to a complete stop at the STOP sign to enter the minor road as shown in the following figure:

A traffic stream is moving at a steady state when entering a mountain grade. Upon entering the grade, the speed, density and flow are 72 km/h, 25 veh/km and 1800 veh/hr respectively. On the grade, a truck drops to a speed of 15 km/h causing traffic to bunch up to a density of 85 veh/km. When the truck pulls over, traffic accelerates to the maximum flow until steady state flow conditions resume. Calculate (a) the flow of traffic behind the truck on the mountain grade (b) the jam density and free flow speed for this road (c) the density and speed when traffic resumes a steady state flow (d) the maximum flow

A major roadway with a speed limit of 35 mi/h has an intersection that has no intersection control with a minor roadway at a right angle. A building is located next to the intersection at a distance of 50 ft from the center of the near lane on the major roadway and 40 ft from the center of the near lane on the minor roadway. At what speed for the minor roadway is the intersection safe? Grades are approximately level.