射线检测技术等级选择应符合制造、安装、在用等有关标准及设计图样规定。承压设备对接焊接

任务型阅读。

     As soon as he amved in New York, Jimmy wanted to make a call to Mother. He found a telephone

booth (电话亭) nearby, put some coins into a box, and dialed 0044181-72486818: Jim was very glad

to say" Hello"to his mother. Just then came a sweet lady's voice behind him.

     "Are you through?"

     "Yes," Jimmy turned and said.

     With a polite "Excuse me", the lady took up the receiver and dialed, Jimmy had to wait outside until

sheput down the receiver.

     After a while, Jimmy dialed again and heard Mother's voice from far away.

     "What's wrong with you? Why did you ring off just now?"

     "I don't know why..." Before Jimmy could finish the sentence a young man ran over and asked

anxiously (焦急地) "Are you through?"

     "Yes."

     With saying "OK", the man quickly set the receiver to his ear and dialed. Jimmy did not know what to

do. Just imagine how worried Mother was in London!         

1. Jimmy came from _____.

2. Jimmy gave a call to his mother at a _____.

3. " _____" meant " Have you finished calling?"

4. Jenny's mother _____ his son.

5. According to the passage, the same words mean _____ meanings indifferent countries.

制备水杨酸对正辛基苯基酯（）如下：

步骤一：将水杨酸晶体投入三颈烧瓶中，再加入氯苯，搅拌溶解后，加入无水三氯化铝。

步骤二：按图12所示装置装配好仪器，水浴加热控制温度在20～40℃之间，在搅拌下滴加SOCl₂，反应制得水杨酰氯，该反应为：

（水杨酸）＋SOCl₂→（水杨酰氯）＋HCl↑＋SO₂↑

步骤三：将三颈烧瓶中的混合液升温至80℃，再加入对正辛苯酚（），温度控制在100℃左右，不断搅拌。

步骤四：过滤、蒸馏、减压过滤；酒精洗涤、干燥。

（1）步骤一中加入三氯化铝的作用是       。

（2）实验时，冷凝管中的水应从    进      出（选填“a”或“b”）；装置c的作用是       。

（3）步骤三��发生反应的化学方程式为　　　　　　　　　　　　。

（4）步骤四减压过滤操作中，除烧杯、玻璃棒外，还必须使用的硅酸盐材料的仪器有　　　　。

（5）步骤四减压过滤时，有时滤纸会穿孔，避免滤纸穿孔的措施是       。

根据以下资料，回答下列问题。

2007年7月份，社会消费品零售总额6998亿元，同比增长16.4%。分地域看，城市消费品零售额4762亿元，同比增长16.7%，县及县以下零售额2236亿元，增长15.8%。

2006年7月城市消费零售额占到社会消费零售总额的比重比县及县以下零售额占社会消费零售总额的比重高多少百分点（）

A．20

B．36

C．42

D．45

为观察某草药对致癌物毒性拮抗作用，将60只大鼠随机分三组，每组20只进行毒性实验，对照组发生肿瘤为0只，致癌物组发生肿瘤为15只，草药+致癌物组发生肿瘤为8只。

计算统计量为（）

A.21.52

B.23.83

C.29.52

D.20.32

E.27.32

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