试论物权法的基本原则。

阅读理解。

     Starting a stamp collection is easy and not very expensive. Before you start, you need to decide

what kind of stamps you want to collect. Most people collect stamps that they are interested in: a

certain country or an animal, a famous person or even a sport. Whatever you choose, you will find

that there is a world of knowledge in stamps: you will learn about people, geography, building, history

and culture.

     You can collect stamps from letters, ask your friends to let you have their old stamps, or you can

buy used stamps. When you get a letter with a stamp on it, carefully cut out the stamp. Leave lots of

space around the stamp so that you will not damage it. Put the stamp in water and wait until you can

safely remove the stamp. Carefully remove the stamp off the letter. Place the wet stamp between two

clean pieces of paper. A stamp can get wrinkled(褶皱的) when it dries, so put some books on top.

1. What does the writer think of collecting stamps?

A. Hard        

B. Expensive          

C. Useful          

D. Boring

2. What does the underlined work "damage" mean?

A. 损坏        

B. 保存              

C. 利用            

D. 删除

3.What's the correct order when we try to get a stamp on a letter?

①Remove the stamp off the letter.

②Place the wet stamp between two pieces of paper.

③Cut out the stamp.

④Put the stamp in water.

⑤Put some books on top.

A. ①→②→⑤→③→④                  

B. ③→④→①→②→⑤

C. ④→①→②→⑤→③                  

D. ③→①→④→②→⑤

在凸透镜左方点燃两支蜡烛，成像于镜右方的方框范围内，如图甲所示，根据实验所得的经验，成像的情形应为图中 

A．

B．

C．

D．

鱼能在天上飞。[ ]

设随机变量X的概率密度函数为

对X进行两次独立观察，其结果分别记为

确定常数A，并计算概率P{X₁＜0，X₂＜1

氮及其化合物在工农业生产、生活中有着重要作用。请回答下列问题

(1)上图是N₂和H₂反应生成2mol NH₃过程中能量变化示意图，请计算每生成1 mol NH₃放出热量为

_____________；

(2)在体积为2L的密闭容器中，进行如下化学反应：N₂(g) +3H₂(g)2NH₃(g) △H<0，得到如下数据

请回答下列问题：

①反应的平衡常数表达式为________； K1的相对大小，K1____(填“>”“=”或“<”)4.1× 10⁶；

②实验l中以v(H₂)表示的反应速率为_____________；

③下列各项能作为判断该反应达到化学平衡状态的依据的是____（填序号字母）；

A．容器内N₂、H₂、NH₃的物质的量浓度之比为1：3：2

B．v(N₂)_正= 3v(H₂)_逆

C．容器内压强保持不变

D．混合气体的密度保持不变

(3)NH₄Cl溶液呈酸性，这是由于NH₄⁺水解的缘故。则NH₄Cl在重水(D₂O)中水解的离子方程式是

__________________