中俄贸易的主要实现形式是( ) A．过境贸易 B．转口贸易 C．边境贸易 D．地方

阅读下列短文，根据短文内容选择最佳答案。

     I have an uncle. He is 22 years old. He was born in Yangzhou. He's very strong and he looks like a

player. He studies in Shanghai. He is good at all his lessons.

    My uncle likes sports very much. He loves football, basketball, baseball, tennis and more. He plays

baseball and basketball very well. He likes to watch the sports games on TV. He does sports every day.

He has a small sports collection (收集). He has 3 tennis rackets, 2 baseballs, 3 basketballs and a football.

1. My uncle _____.

A. works in Shanghai

B. studies in Yangzhou

C. likes sports

D. loves small sports

2. He plays _____ very well.

A. football and basketball

B. the violin

C. baseball and basketball

D. the piano

3. He likes to watch the sports games _____.

A. on the playground

B. on TV

C. at school

D. in Shanghai

4. He plays sports _____.

A. once a week

B. twice a week

C. every day

D. five days a week

5. From the paragraph (文章),we know that my uncle is _____.

A. a good worker

B. a good student

C. a good teacher

D. a good singer

（1）氢气是最轻的气体，难溶于水．氢气作为未来的理想能源，是航天工业的高能燃料，也是化工生产的重要原料．实验室通常采用下面装置制取少量氢气，请根据

要求回答：

①实验室使用稀盐酸和金属锌制取氢气的化学反应方程式为______，这种方法制得的氢气往往含有少量______（原因是______）和水蒸气，可将杂质气体通过装置______除去；

②实验中可采用______装置收集氢气；集满氢气后的集气瓶按装置G方式放置备用，原因是______．

（2）某校课题研究小组到电镀厂考察，了解到铁件镀铜的主要工艺流程如下：

结合流程中提供的信息回答：

①流程Ⅱ废水中含有的物质有______；

②经测定：流程Ⅳ中废水的pH为4，废水中一定没有______；

③流程Ⅳ废水中除流程Ⅰ、Ⅱ引入的物质外，还含有______；

请设计简单方案来证明你的推断：______．

被称为自然资源“大仓库”的是[ ]

A．北极地区    

B．南极地区    

C．亚洲地区    

D．非洲地区

(三)
某工程建设项目施工招标，投标有效期60天，预计中标价格约为2亿元人民币。
问题
根据有关规定，提出该项目招标文件投标保证金的有关具体要求：①投标保证金形式(任选一种)；②投标保证金数量；③投标保证金的递交时间；④投标保证金有效期；⑤不按要求递交投标保证金的后果；⑥投标保证金退还时间；⑦投标保证金不予退还的情形。

在分析食物中毒的可疑食物时，最常用的指标是（）

A.总发病率

B.二代发病率

C.患病率

D.病死率

E.吃不同食物的罹患率