清单计价法的施工机械台班单价构成包括（） ["台班折旧费","台班大修理费和经常修理费","台班人工费","台班燃料动力费和车船税费","台班安拆费及场外运输费"]
生物群落所具有的基本特征有哪些？
Which statement is true concerning 6to4 tunneling?（） [" The edge routers can use any locally configured IPv6 address."," Hosts and routers inside a 6to4 site will need a special code."," An edge router must use IPv6 address of 2002::\/16 in its prefix."," IPv4 traffic is encapsulated with an IPv6 header."]
At which layer of the OSI model is the optimal path to a network destination determined at?（） [" Data Link"," Session"," Physical"," Presentation"," Network"," Transport"]
如何确定公债发行条件？
失去外在水分的煤称为（）。
