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频率是单位时间内完成振动的次数，是描述振动物体往复运动频繁程度的量，为了纪念德国物理学家赫兹的贡献，人们把频率的单位命名为赫兹，简称“赫”。For that reason , pursuance of sea power with no authorization from the UN is completely hegemonic behavior.Tipos de cartas de citación: So