观察下列分母有理化的计算：12+1=2-113+2=3-214+3=4-315+

仔细观察下图，下列有关说法正确的是

A．图中b区的直链烷烃在常温下呈液态

B．烷烃的熔点随分子中碳原子的增加一定逐渐升高

C．汽油的化学成份为C5～C12的碳氢化合物，分馏石油时，收集汽油的温度应控制在200℃以上

D．碳原子数相同的不同烷烃，其沸点都相同

松果体中与生物节律有关的生物活性物质是（）

A.神经降压素

B.升压素

C.激肽

D.褪黑激素

E.促黑激素

男，50岁。因交通事故造成面中份创伤，有短暂昏迷史，临床检查：面中1/3凹陷，咬合错乱，影像学检查符合上颌骨LeFortⅢ型骨折

现场抢救时，若发生窒息，最实用的抢救方法是（）

A.环甲膜切开后，气管切开

B.迅速经口或鼻腔气管插管

C.舌体牵出口外，纠正舌后坠

D.清除口鼻腔及咽喉部血块、呕吐物等

E.用压舌板横放于上前磨牙，并固定于头部绷带

阅读理解。

     I travel a lot, and I find out different "styles" (风格) of directions every time I ask "How can I get to the

post office?"

     Foreign tourists are often confused (困惑) in Japan because most streets there don't have names; in Japan,

people use landmarks (地标) in their directions instead of street names. For example, the Japanese will say to

travelers, "Go straight down to the corner. Turn left at the big hotel and go past a fruit market. The post office

is across from the bus stop."

     In the countryside of the American Midwest, there are not usually many landmarks. There are no mountains,

so the land is very flat; in many places there are no towns or buildings within miles. Instead of landmarks,

people will tell you directions and distances. In Kansas or Iowa, for example, people will say, "Go north two

miles. Turn east, and then go another mile."

     People in Los Angeles, California, have no idea of distance on the map; they measure distance in time, not

miles. "How far away is the post office?" you ask. "Oh," they answer, "it's about five minutes from here." You

say, "Yes, but how many miles away is it?" They don't know.

     It's true that a person doesn't know the answer to your question sometimes. What happens in such a

situation? A new Yorker might say, "Sorry, I have no idea." But in Yucatan, Mexico, no one answers "I don't

know." People in Yucatan believe that "I don't know" is impolite. They usually give an answer, often a wrong

one. A tourist can get very, very lost in Yucatan!

1. When a tourist asks the Japanese the way to a certain place, they usually _____.

A. describe the place carefully

B. show him a map of the place

C. tell him the names of the streets

D. refer to recognizable buildings and places

2. What is the place where people measure distance in time?

A. New York.

B. Los Angeles.

C. Kansas.

D. Iowa.

3. People in Yucatan may give a tourist a wrong answer _____ .

A. in order to save time

B. as a test

C. so as to be polite

D. for fun

4. Which sentence is true according to the text?

A. There is no street names in Japan.

B. There is no landmarks in the countryside of American.

C. People in Yucatan always give wrong answers when asked the way.

D. People in Los Angeles measure distance in time, not miles when asked the way.

5. What can we infer from the text?

A. It's important for travelers to understand cultural differences.

B. It's useful for travelers to know how to ask the way properly.

C. People have similar understandings of politeness.

D. New Yorkers are generally friendly to visitors.

地质灾害