25. 用标距50mm和100mm的两种拉伸试样,测得低碳钢的屈服应力分别为σs1和σs2,延伸率分别为δ5和δ10,比较两试样的结果,则有( )
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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