Various substances differ widely in their magnetic(磁性的) characteristics.

Various substances differ widely in their magnetic(磁性的) characteristics.

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雷云对大地的放电电流很大,电流的热效应使放电电流通道的温度高达数万度,造成火灾及破坏其他物体。A.正确B.错误

雷云对大地的放电电流很大,电流的热效应使放电电流通道的温度高达数万度,造成火灾及破坏其他物体。A.正确B.错误

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下面()属于基本安全用具A.绝缘棒B.绝缘垫C.绝缘夹钳D.验电器

下面()属于基本安全用具A.绝缘棒B.绝缘垫C.绝缘夹钳D.验电器

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We're running behind schedule by about 15 minutes.

We're running behind schedule by about 15 minutes.

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