This is the research　　　many scientists attach importance.

根据表格内容完成下面的短文，每空词数不限。

    Scott doesn't go to work on Sunday. On Sunday morning, he usually gets up late. He gets up at ____. After breakfast, he usually reads books or listens to music for ____. After that, he often ____ with his friends. In the afternoon, Scott ____ from 3:00 to 5:00. The Sunday evening is relaxing for Scott. He usually ____. Scott needs a good sleep. So he ____ and goes to bed at ____.

读一读，选择一个词语造句。

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七年级3班小奇同学进行研究性学习，他搜集了“贞观之治”、“开元盛世”、“玄奖西游”、“鉴真东渡”的相关资料，由此推断他研究的课题是（    ）

 实验室中有一瓶含有少量氯化钠和可溶性杂质的硫酸钠样品．某化学兴趣小组对该样品成分进行定量测定，甲、乙、丙三位同学分别称取一定质量的样品放入烧杯中，溶入足量水后过滤得到滤液；再向滤液中加入一定质量的氯化钡溶液，充分反应后过滤，将沉淀洗涤、干燥并称量．相关实验数据记录如下：

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