GB3811-2007规定;载流零线可以通过金属结构、轨道、设备连接构成回路;
正确
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Notreally.Itisshrewdbusinessoperations.
Thereisno( )betweenthenations.
Sitbackandreflecton______itisthatyoudobestandwhatyouenjoy.
Ifhe____ontouristsforhisbusiness,hewouldhavetoclosehisshop.
Whatmakesameetingeffective?