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问题 选择题

甲、乙两种固体的溶解度曲线如图所示．下列说法中正确的是

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A．20℃时，甲溶液中溶质的质量分数等于乙溶液中溶质的质量分数

B．20℃时．将相同质量的甲溶液和乙溶液分别恒温蒸发等质量的水，析出晶体的质量ma=mb

C．40℃时，分别在100水中加入30g甲和30g乙同时降温至20℃，甲、乙溶液均为饱和溶液

D．20℃时，分别在100g水中加入40g甲、乙，加热到40℃时，甲溶液为饱和溶液

答案

答案：C

单项选择题 A1型题

我国对化妆品生产和销售实行法制管理开始于（）。

A.20世纪50年代

B.20世纪60年代

C.20世纪70年代

D.20世纪80年代

E.20世纪90年代
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听力题

根据短文内容及首字母提示，填写所缺单词，使短文意思完整，每空只填一词。

Millions of American children attend summer camp. Traditional American summer camps offer young people a c_______小题1: to play many sports. These camps may be in the mountains. Or they may be in the woods, or at a lake. O_______小题2:  camps teach activities like painting or music. Or t________小题3:teach computer programming or foreign languages. Children at all kinds of camps m_________小题4: new friends. They learn new skills and develop independence (独立).

Some children go to camp d_______小题5: the day and return home at night. These places are c______小题6: day camps. Children as y_________小题7: as four years old attend day camps. Others stay at camp all day and all night. Most children w_________小题8: attend overnight camp are between the ages of about six and sixteen.

Children s________小题9: at an overnight camp for between one and eight weeks. P________小题10: can pay less than one-hundred dollars a week for an overnight camp. Or they can pay more than seven-hundred dollars a week.
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