6. Calculate the "clearance period," the "yellow time," and the "all-red period" for a signalized intersection. Assume that the initial vehicle speed, intersection length, and vehicle length are 45 mi/h, 44 ft, and 22 ft, respectively. (25 points) 7. An approach at a pretimed signalized intersection is allocated 30 seconds of effective green in an 80-second signal cycle. The flow at the approach is 500 veh/h and the saturation flow of the approach is 2500 veh/h. Assuming D/D/1 queuing, calculate: 1) the time needed to clear the queue, 2) the average delay per vehicle, and 3) the maximum delay of any vehicle. (25 points) 8. Consider the intersection in problem 7 above which works in isolated mode. Calculate the average delay per vehicle using the Highway Capacity Manual (HCM) formula. Assume the traffic flow accounts for the peak 15-minute period and that there is no initial queue at the start of the analysis period. (25 points)