Bonus (15pts)A traffic signal has a 60-second cycle length. For the travel direction of interest, the effective red and green times are 30 seconds each, the arrival rate is constant (i. e. no random fluctuations) at 20 vehs/min and the saturation flow (i. e., the queue discharge rate) is 1 veh/sec. a)Calculate the average delay for the travel direction of interest. b)Assume work on the street is taking place downstream of the intersection so that only 25 vehs/min (in the direction of interest) can pass. Calculate the average delay caused by the street work to a vehicle leaving the intersection. Assume that the queue atthe downstream restriction never backs-up into the intersection.