一根悬臂梁长2m,在悬臂梁的顶端受到1KN的作用力,则在其固定端截面的弯矩为2000N.m。
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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