（10分）把一条铁链自由下垂地悬挂在墙上，铁链长为25m，在铁链正下方距铁链下端

阅读理解。

     Do you know why you sleep? You may think it's because you're tired. Or perhaps you've been told sleep

is good for you. Yet no one knows exactly why or how people sleep.

      Until the early 1950s, most scientists thought the body and brain rested during sleep. Then a scientist

watched people sleep. He noticed that during periods of between 5 and 30 minutes, sleepers' eyes made

rapid movements, as if they were watching something. He called these periods REM (Rapid Eye Movement)

sleep. He called periods when sleeper's eyes did not move non-REM sleep.

     Whenever the scientist woke people during REM sleep, they were having vivid dreams. Measurements

showed that sleepers' pulses (脉搏) went up quickly during REM sleep. Their breathing, heartbeat, and the

blood going to the brain also increased. Far from being a time of rest, sleep is a time when the body is hard

at work. Scientists still don't know the reason for this. Some believe REM sleep makes learning easier.

Babies spend a lot of time on REM sleep. Because of this, some scientists believe that REM sleep helps

the brain grow. Others think REM sleep is a time for the brain to empty the day's garbage.

      One thing all the scientists agree on is that sleep is necessary. Without enough sleep, people make

mistakes. Most car accidents happen during the early morning hours, when people are sleepiest.

1. During REM sleep, a person's breathing and heartbeat ______.

A. stop

B. sleep

C. increase

D. stay the same

2. The underlined word "vivid" means ______.

A. easier

B. large

C. empty

D. clear anti lively

3. ______ tells what happens when people don't get enough sleep.

A. Paragraph 1

B. Paragraph 2

C. Paragraph 3

D. Paragraph 4

4. The main idea of this passage is ______.

A. that REM sleep can help the brain grow

B. about the scientific research of REM sleep

C. about how to empty the day's garbage

D. that our body is good at work when sleeping

5. We can know from the passage that _______.

A. enough sleep is very important to people

B. young people can experience REM sleep

C. the speed of sleepers' pulses will slow down during the REM sleep

D. all scientists have the same opinion on REM sleep

可使热性惊厥患儿转变为癫痫的危险因素是（）

A.首次发作为单纯性热性惊厥

B.有热性惊厥家族史

C.直系亲属中有癫痫病史

D.首次发作前神经系统发育正常

E.以上都不是

下列财产中，属于房地产的有()。

A.房地产开发用地

B.种植在房前的树 

C.挂在墙上的画

D.安装在房屋中的水暖设备 

E.摆放在室内的家用电器

小三角测量内业计算的最终目的是（）。

A.求各三角点的坐标

B.求三角形边长

C.求三角形的各内角及边长

D.求三角形的内角

双标记法荧光抗体技术的主要用途是

A．提高荧光强度

B．提高荧光效率

C．可同时检测同一标本中两种抗原

D．使用一种标记物可检测多种抗原

E．减少非特异性荧光