血吸虫病的传播方式是（） A.消化道为主 B.呼吸道 C.呼吸道和消化道 D.皮肤黏

阅读理解。

     There are many wetlands in China and some of them have become internationally important wetlands.

The Chinese Yellow Sea Wetlands are one example. They are in Yancheng, Jiangsu Province. They are

the ideal home for many different  kinds  of   birds  and   animals. The  world's largest  Milu Deer Nature

Reserve is there. More than 700 milu deer live freely there.   There are not many red-crowned cranes in

the world, but every winter you can see some in the Red-Crowned Cranes Nature Reserve in the

Yellow Sea Wetlands.

     The temperature in the wetlands is usually not too high or too low.  There is a lot of rain and sunshine,

too. They are really good places for wildlife. They offer food and home for some special kinds of animals

and birds. It is not the only reason why we need to   protect  wetlands.  Wetlands are important because

they also   prevent   floods. But   some people want to change the wetlands to make space for farms and

buildings. This means there will be less and less space for wildlife.

     Luckily, more and more people are beginning  to   realize  the  importance of wetlands  and  wildlife.

Every year on February 2nd, the World Wetlands  Day,  many  activities are  held  to  tell  people  more

about wetlands.

1. Which of the following is the ideal home for birds and animals?

A. The Yellow River.  

B. The wetlands.  

C. North China.    

D. Cities in China.

2. What's the weather like in the wetlands?

A. It's very hot.    

B. It's too cold.  

C. There's a lot of snow.    

D. It rains a lot there.

3. Why are the wetlands good places for wildlife?

A. Wildlife can find food and home there.

B. All wildlife can live freely there.

C. There' re enough friends for them.

D. There is enough room for them.

4. What's the use of the wetlands?

A. To raise(饲养) more wildlife.            

B. To prevent floods.

C. To offer lots of food for human beings.    

D. A and B.

5. Which of the following is Not true?

A. More than 700 milu deer live freely because of the wetlands.

B. We can't see red-crowned cranes in the Yellow Sea Wetlands.

C. February 2nd is the World Wetlands Day.

D. People are beginning to realize the importance of wetlands.

某小岛上原有果蝇20000只，其中基因型MM、Mm和mm的果蝇分别占15%、55%和30%。若从岛外入侵了2000只基因型为MM的果蝇且所有果蝇均随机交配，则F₁代中m的基因频率约是[ ]

A．43%

B．48%

C．52%

D．57%

（10分）用规范的化学语言回答下列问题：

（1）过氧化钠跟CO₂反应的化学方程式                                     。

（2）一定条件下，乙醛可跟氢气反应生成乙醇，该反应的反应类型是           。

（3）氯化铵溶液呈酸性的原因（用离子方程式回答）                         。

（4）氢氧化镁浊液中的溶解沉淀平衡方程式                                 。

（5）氯碱工业中用电解饱和食盐水的方法制取烧碱和氯气，该电解过程中的电极反应方程式为：阳极                   ，阴极                   。

数据流图用于抽象描述一个软件的逻辑模型，数据流图由一些特定的图符构成。下列图符名标识的图符不属于数据流图合法图符的是( )。

A．控制流

B．加工

C．存储文件

D．源和潭

既能健脾渗湿，又能消痈排脓的药是

A．木通
B．薏苡仁
C．车前子
D．滑石
E．茯苓