【答案】B。
解析：物流服务收费要看公里数以及包裹重量，所以Vehicle cost per kilometre-kilogram可以作为物流公司的cost unit。每公里的油费也可以是cost unit，公里数越多油耗越高，且货物越重油耗也会越高。Maintenance cost for each vehicle不仅跟里程数和重量有关，更与路面状况、事故、驾驶员、车辆性能等因素密切相关，所以不适合做cost unit。
知识点：Service costing (Chapter 10 Job, batch and service costing)
【答案】B。
解析：Total room-night available for the latest two-week period: 50×14 = 700
Occupied room-night: 700×70% = 490
Room cleaning cost per occupied room-night for the period = 3,600/490 = $7 per room-night
知识点：Service costing (Chapter 10 Job, batch and service costing)
