第一节听下面5段对话。每段对话后有一个小题，从题中所给的A、B、C三个选项中选出最佳选项，并标在试卷的相应位置。听完每段对话后，你都有10秒钟的时间来回答有关小题和阅读下一小题，每段对话仅读一遍。 What is the man’s occupation now
A. He’s a secretary.
B. He’s a novelist.
C. He’s a newspaperman.
查看答案
在算法的4个特征中，算法必须能在执行有限个步骤之后终止，指的是算法的______性。
Questions 23 to 25 are based on the conversation you have just heard.
A. She had her vacation there.
B. She took a diving course there.
C. She was there on a field trip.
D. She visited a marine exhibition.
沉淀称量法中的称量式必须具有确定的化学组成。( )
A. 对
B. 错
在进行沉淀时，沉淀剂不是越多越好，因为过多的沉淀剂可能会引起同离子效应，反而使沉淀的溶解度增加。( )
A. 对
B. 错
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