网关的作用是实现 【1】 的转换。

根据短文内容及首字母提示完成所缺的单词。

     Many people believe that the hump (驼峰) of a camel is full of water. They believe this is the r 1    

that camels do not have to drink very often, but they are quite wrong. A camel's hump is not full of water.

It is mostly fat. The camel's b  2     can use the fat later when it is hungry, but it does not help the camel

go for a long time without d  3   . A camel can do this because it does not sweat(出汗) very much.

     When people and most other animals-get h  4   , they sweat. Sweat is mostly water from the body.

So, when people sweat, they l  5   water and soon have to drink. If they do not drink water, they will

die. When a camel gets hot, it does not sweat very much, so it does not lose m  6     of the water in its

body. It does not need to drink very often.

     There is very little water in the desert, so a  7     animal that does not need much water is very useful

for c   8   people and things across the desert. Camels can t   9   a long way without stopping for food

or water. This is w  10     the camel is called ” The Ship of the Desert."-it carries its food and water with

it, and it can go for a long Lime between towns.

1. ________2. ________3. ________4. ________5. ________

6. ________7. ________8. ________9. ________10. ________

一辆长为l₁=5m的汽车以v₁=15m/s的速度在公路上匀速行驶，在离铁路与公路交叉点s₁=175m处，汽车司机突然发现离交叉点s₂=200m处有一列长为l₂=300m的列车以v₂=20m/s的速度行驶过来，为了避免事故的发生，汽车司机立刻使汽车减速，让火车先通过交叉点，求汽车减速的加速度至少多大？（不计汽车司机的反映时间）

下列关于钾代谢的说法错误的是（）

A.正常成人血清钾浓度为3.5～5.5mmol/L

B.维持细胞内渗透压

C.多吃多排，少吃少排，不吃则不排

D.大部分经肾排出

E.血清钾高时对心肌有抑制作用

影响食管癌放疗疗效的因素是（）

A.病变长度

B.X线病理分型

C.年龄

D.有无锁骨淋巴结转移

E.以上全是

平稳随机过程必须（）。

A.连续

B.统计特征与时间无关

C.各态历经

D.统计特征等于时间平均