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当前学科:通信工程师综合练习
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避雷针或与避雷针有电气连接的金属抱杆,应采用直径不小于()mm多股铜导线或40×4mm的镀锌扁钢可靠接地,严禁采用铝线。
A . A、70
B . B、95
C . C、120
D . D、150
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