When traffic is very heavy, congestion also builds at the entry to the toll plaza because of the time required for each vehicle to pay the toll. 當交通量非常大的時(shí)候，因為每車(chē)輛付通行費的時(shí)間要求，阻塞也會(huì )出現在收費區的入口處。
Make a model to help you determine the optimal number of tollbooths to deploy in a barrier-toll plaza. 建立一個(gè)模型來(lái)確定在一個(gè)容易造成阻塞的收費區中應該設置的收費亭的最優(yōu)數量。
It can be in a vending or gumball machine, pay phone or toll plaza. 地點(diǎn)可以是自動(dòng)販賣(mài)機或是糖果機，，投幣電話(huà)機或收費廣場(chǎng)。
