泥石流的形成条件:( ) 1.地势陡峻、纵坡降较大的山区 2.地质构造复杂3.崩塌滑坡灾害多 4.暴雨 5.地表径流平缓
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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