某混凝土预制构件厂,生产钢筋混凝土大量需用设计强度为C30的混凝土,已知混凝土强度标准差为4.0MPa,则混凝土的配制强度为36.58MPa。
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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