某癌病专家及其同事一起为一食道癌病人做了开胸手术。第二天早上交班时，这位专家问当班护

下面四幅图的比例尺，最大的是[ ]

A．1：25000000

B．1：6700000

C．1：2500000

D．1：9800000

在高效课堂中，老师和同学们一起对“灭火的原理”进行了探究学习。

【课堂归纳】(1)通过小组合作实验，我们归纳出燃烧的三个条件是：①可燃物②___________③________

【演示引导】我们进一步学习灭火的原理。如下图所示，烧杯中有一支燃着的蜡烛，烧杯底部有一些碳酸钠粉末，向烧杯中倒入少量稀盐酸，发现蜡烛迅速的熄灭。写出上述反应的化学方程式是__________________________________。 熄灭蜡烛所依据的原理是___________________________。

【小组探究】点燃一长一短两支蜡烛，同学们分小组对熄灭蜡烛的方法展开探究。

(2)小何说：“因为人呼出的是二氧化碳气体，所以我可以将它们吹灭。” 小邹对小何的说法提出了质疑，认为人呼出的气体中含有氧气，并设计如下实验证明了自己的说法。

看了小邹的实验后，小何发现了吹灭蜡烛所依据的灭火原理是____________________。(3)小丽说：“可以在燃着的两支蜡烛上罩一个大烧杯，过一会蜡烛也会熄灭。”（如下图）

小苗说：“蜡烛熄灭是有先后顺序的，因为蜡烛燃烧会产生二氧化碳，二氧化碳的密度比空气大，所以短蜡烛先熄。”小张说：“由于氧气的密度比空气大，上部氧气少，所以长蜡烛先熄。”同学们一起合作进行了实验，发现长蜡烛先熄。小苗对小张的说法仍心存疑惑，认为氧气的密度比空气大不是长蜡烛先熄的主要原因，并设计实验进行了证明。她的实验方案是_______________________________________________________________。通过实验，小苗终于发现了长蜡烛先熄灭的秘密，她的发现是___________________________。(4)通过探究，小丽进一步提出采用与上述灭火原理不同的方法是___________________。【归纳反思】通过学习，我知道了灭火的原理，而且还有了新的启示是___________。（答一条）

北半球海洋某处，地磁场水平分量B₁=0.8×10^－4T，竖直分量B₂=0.5×10^－4T，海水向北流动。海洋工作者测量海水的流速时，将两极板竖直插入此处海水中，保持两极板正对且垂线沿东西方向，两极板相距L=20m，如图所示。与两极板相连的电压表（可看作理想电压表）示数为U=0.2mV，则

A.西侧极板电势高，东侧极板电势低，且海水的流速大小为0.125m/s

B.西侧极板电势高，东侧极板电势低，且海水的流速大小为0.2m/s

C.西侧极板电势低，东侧极板电势高，且海水的流速大小为0.125m/s

D.西侧极板电势低，东侧极板电势高，且海水的流速大小为0.2m/s

阅读理解

     Welcome to Language upon Thames.  This brochure has been designed to give you an overview of our Language School and the courses we offer. If you have some additional questions please do not hesitate to contact us for more information.

     At Language upon Thames, we feel it is important to be flexible, in order that students can decide what period of study suits them best.

                           Small Group General English Courses

     These courses are aimed at students who wish to improve their speaking, listening, reading and writing

skills and are offered at the following levels.

     BEGINNERS

     ELEMENTARY (初级)

     PREINTERMEDIATE

     UPPERINTERMEDIATE

     Studying one of the above courses will enable you to use English more confidently and competently

on a daily basis.

     Try our free online test to see which level you are at-CLICK HERE.

                            Exam Courses

     These courses are aimed at students who wish to gain academic qualifications in English and are offered at the following levels.

     University of Cambridge exams:

     ADVANCED 1-FCE (First certificate)

     ADVANCED 2-CAE (Advanced)

     ADVANCED 3-CPE (Proficiency)

     Studying one of the above courses will enable you to continue your education or enter university in this country. (Students wishing to gain admission to a British university are normally required to have the

Cambridge Proficiency Certificate.)

                            Speaking, Listening & Pronunciation

      This course builds on communicative confidence and competence and is aimed at students who wish to develop the important skills of speaking and listening.

      Emphasis is also placed on pronunciation, with activities designed to meet the needs of students of

different nationalities, who need to focus on different areas.

      CLICK HERE to register for a General English course.

                          Other Languages

      At Language upon Thames we offer a wide range of cafeterias, restaurants, shops and bars. Most

importantly, we have foreign language classes of French, Japanese, German, Spanish and Italian during the day, evening or on a onetoone basis.

1. What does this passage mainly talk about?

A. English courses.

B. Ways to improve students' English.

C. The best way to improve your skills.

D. The importance of English.

2. If you attend Exam Courses, you will ________. 

A. use English as fluently as a native speaker

B. deal with everyday English well

C. have better pronunciation of English

D. be able to continue your education or enter university in this country

3. Judging from the description, we can tell that this passage must be taken from ________. 

A. a newspaper              

B. a magazine

C. the Internet              

D. a guidebook

4. The following statements are true EXCEPT ________. 

A. only Englishmen can attend the courses

B. the courses are designed for learners of different levels

C. one can learn French even in the evening

D. Language upon Thames is a school aimed to offer help with language learning

并联电阻可以用来分压。（）