一架飞行时与一只秃鹰相撞。飞机质量为m0 ,飞行速度大小为v=500m/s,秃鹰质量m=1kg,身长为20cm,则秃鹰对飞机的冲击力为()。
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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