Observation 2 下四 dI) z Delay t custom 2 B() custom I t2 13 t67 Shaded Area= total time that all the customs spend in the system B(t) T;+ B(t)+1Communication Networks Observation 2 9 Shaded Area = total time that all the customs spend in the system ෍𝑖=1 𝛽 𝑡 𝑇𝑖 +෍𝛽 𝑡 +1 𝛼 𝑡 𝑡 − 𝑡𝑖 Number of Arrivals a(t) Number of Departures b(t) custom 1 Delay T1 custom 2 Delay T2 a(t) b(t) t1 t2 t3 t4 t5 t6 t7 t t