粘性土的抗剪强度由________和粘聚力两方面因素组成。

阅读理解。

     Last Sunday the Greens went to the movies. They got home very late. Father opened the front door

and went into the house. It was very dark, so mother turned on the light. On the way to their bedroom,

mother said, "Listen, John! I can hear someone in the bedroom. " They all stood quietly outside the

bedroom. They could hear some voices (声音) in the room.

     "You are right. " father said, "There are two men in it. They are talking. " Then he shouted, "Who's

there?" But no one answered. Father opened the door quickly and turned on the light. The room was

empty. Then father found something and laughed. "The TV is still on (开着的). I forgot to turn it off (关)

this morning!" father said.

( )1. The Greens got home very early.                                  

( )2. On the way to their bedroom, mother heard someone in the bedroom.

( )3. They all stood quietly in the bedroom.                          

( )4. There were really two men talking in the room.                  

( )5. Father opened the door slowly and turned on the light.          

6月5日是世界环境日，今年我国的世界环境日主题是“共建生态文明、共享绿色未来”。草原是绿色生态环境的组部分。某草原生态系统的食物网如图所示。

(1)图中食物网的简单，因此，该草原生态系统的_________能力较差，其_______稳定性也相应较低。除图中所示的生物类群外，该生态系统的生物组成成分还应有________才能保证其物质循环的正常进行。

(2)如果图中草能提供10000KJ的能量，营养级间的能量传递效率为10%～20%，那么鹰占据的营养级能得到的最低和最高能量值分别是______KJ和______KJ。若去除蛇，且狐的数量不变，则草原容纳鹰的数量会__________。若外来生物入侵该区，则会导致草原的__________锐减或丧失。

(3)影响图中兔种群数量变化的种间因素是__________和竞争。若某年兔种群的K值为1000只，且1只兔和4只鼠消耗的草量相等，其他条件不变的情况下，次年鼠的数量增加400只，则兔种群的K值变为____只。用标志重捕法调查该区的种群数量时，若部分标记个体迁出，则导致调查结果_______(填“偏高”或“偏低”)

(4)草原干旱时，兔摄取水分减少，体内细胞外液渗透压________，引起__________渗透压感受器兴奋，增加抗利尿激素的释放，进而引起__________对水的重吸收增加，减少排尿量,以保持体内水平衡。

根吸收水和无机盐的部位主要是根尖的（   ）

A．根冠

B．伸长区

C．成熟区

D．分生区

事故等级如何划分？

影响利率水平的因素有( )。

A．货币资金供求关系

B．中央银行货币政策

C．通货膨胀率

D．储蓄与投资两大因素的相互作用

E．历史的沿革