题目

Africa is a very diverse land with many different tribes. One tradition that many of these groups share is painting or marking their bodies and faces in color. They do this for many reasons. Some marks are used to identify people as part of a group.__36___ Let’s look at some different examples of body painting.    ____37___ Among the Masai of East Africa, when men are old enough to marry and make decisions for their people, they participate in a special ceremony in which they paint their heads and faces red. This ceremony takes place every seven to fourteen years, so there is not a某课外兴趣小组对一批铁样品（所含杂质不与稀硫酸反应）进行分析，甲、乙、丙三位同学分别进行实验，其中只有一位同学所取用的稀硫酸与铁样品恰好完全反应，实验数据如表．（1）三位同学中，恰好完全反应是 同学的实验，该实验中产生 g氢气．（2）样品中铁的质量分数是多少？（计算结果精确到0.1%）组别编号甲乙丙烧杯+稀硫酸200g150g150g加入的铁样品9g9g14g充分反应后，烧杯+剩余物208.7g158.7g163.7g