For large shipments even if less than a full truckload, a truck is more appropriate.( )
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For transport of hazardous materials truckers need a license, which usually require them to pass an exam.( )
A. 对
B. 错
实验中,根据不同的称量对象和不同的天平,需要采用不同的称量方法,常用称量方法一般有____、____、____。
分析天平的操作步骤分为____、____、____、____、____、____。
称量前,应确保天平的水平泡是否在____,如有需要则通过____将水平泡调至中心。
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