一段导线,其电阻为R,将其从中对折合并段新的导线,则其电阻为( )
有一段16Ω的导线,把它们对折起来作为一条导线用,其电阻是( )。
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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