若用P表示高强度螺栓预拉力,f表示钢材表面的摩擦系数,m表示连接处的摩擦面数,K表示安全系数,则高强度螺栓的容许荷载可用下列()表示。
You can _____ some bottles of wine, or some chocolates, or a bunch of flowers.
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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