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问题 单项选择题

3，5-Br2-PADAP分光光度法测定水中银时，水样中相对于银含量（）倍的铝（Ⅲ）对银的测定无影响。

A．200

B．500

C．1000

D．1200

答案

参考答案：C

改错题

短文改错(共10小题，每小题1分，满分10分)

假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，每句中最多有两处，每处错误仅涉及一个单词的增加、删除或修改.

增加：在缺词处加一个漏字符号（∧），并在其下面写出该加的词。

删除：把多余的词用斜线（＼）划掉。

修改: 在错的词下划一横线,并在该词下面写出修改后的词。

注意: 1、每处错误及其修改均限一词。

2、只允许修改10处,多者(从第11处起)不计分。

It was Monday. Li Ming was the first come to the classroom. When he came into his seat, therefore, he found his bench was broken. Seen there was nobody around, he decided to change it with Wang Gang’s, and so he did. After a while, Wang Gang came. When he saw a broken bench, he carried it out of the classroom. Li Ming didn’t know how he was going to do. So Li Ming came out of and found that Wang Gang has begun to repair the broken bench. Li Ming’s face turn red. He said with Wang Gang, “Let’s repair them together.”
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选择题

欲鉴别氢气、氧气、二氧化碳、甲烷4种气体，现有一盒火柴，还需要用到下列实验用品中的[ ]

A．装有蒸馏水的烧杯

B．装有无色酚酞的烧杯

C．冷而干燥的烧杯

D．内壁蘸有澄清石灰水的烧杯

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