单项选择题

发电厂人工接地装置的导体，应符合热稳定与均压的要求外，下面列出的按机械强度要求的导体的最小尺寸中，哪项是不符合要求的？（ ）

A.地下埋设的圆钢直径8mm
B.地下埋设的扁钢截面48mm2
C.地下埋设的角钢厚度4mm
D.地下埋设的钢管管壁厚度3.5mm
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Section A Dialogue CompletionDirections: In this section, you will read 5 short incomplete dialogues between two speakers, each followed by four choices marked A, B, C, and D.Choose the answer that best suits the situation to complete the dialoguE.Mark your answer on the ANSWER SHEET with a single line through the center.Speaker A: I need to make a hotel reservation for my father. Speaker B:______A.Why does your father want to stay in a hotel?B.Is your father going abroad?C.But do you know how to make a reservation?D.How about calling the travel agency?
A.Speaker
B.Why
C.Is
D.But
E.How
单项选择题
某发电厂300MW机组的电能计量装置，其电压互感器的二次回路允许电压降百分数不大于下列哪项数值？（ ）
A.1%～3%
B.0.2%
C.0.45%
D.0.5%
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