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问题 单项选择题

为了防止爆炸性混合气体的形成，氧化反应器升温投料前要认真检查核准投料程序，严格控制投料比，要（）

A.先投空气，再投氨

B.先投氨，再投空气

C.同时投入氨气和空气

答案

参考答案：A

完形填空

San Francisco has many museums. You can visit one and learn s  小题1:   new. We have arts, science, history and other special museums. Some museums are o 小题2:   every day. Some are only open o 小题3:   certain days. Many museums are expensive, and others are f 小题4: . But some of the expensive o 小题5:   have free days. Many museums have websites. The websites usually have information about the things you can see in the museums.

On a museum’s website you can get i 小题6:  about ticket prices and free days. You can also know w  小题7:   the museum is and when it is open. Sometimes the information is on the first page, and it’s very e 小题8:  for you to find. But sometimes you have to click on (点击) the w 小题9:   like Visit Information, or About to find the information. That will be hard w 小题10:    for you.
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选择题

读城市等级与服务范围模式图，回答1～2题。

1．下列商业部门与图中所属城市对应正确的是 [ ]

A．甲为普通服装店　乙为家具商店　丙为五星级宾馆

B．甲为汽车销售点　乙为早点店　丙为高级家用电器店

C．甲为珠宝行　乙为家具商店　丙为早点店

D．甲为早点店　乙为五星级宾馆　丙为珠宝行

 2．关于城市等级与其服务范围的叙述，正确的是

①城市一定位于城市服务范围的几何中心

②高一级城市的服务范围被低一级城市的服务范围所覆盖

③城市服务范围的大小与其等级成正比

④在市场原则下，高一级中心地的服务范围相当于三个低一级中心地的服务范围 [ ]

A．①②

B．③④

C．①③

D．②④

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