HELPING THE OTHERS REALIZE THE ADVANTAGES OF LA CARTA

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”。Marty Shepard then came aboard on trumpet, quickly joined by a second trumpeter named Steve (final name unknown). Doughty joined them as a 3