成人胸外心脏按压的正确位置是（）。 A.胸骨下段 B.剑突 C.心前区 D.心尖部

一张长方形图片，长1她厘米，宽9厘米．按1：3的比缩小后，新图片的长是______厘米，宽是______厘米，这张图片______不变，大小______．

为什么不选择穿刺颈外静脉插入漂浮导管，原因是（）

A.由于入锁骨下静脉处呈钝角，置管多不顺利

B.经此途径插入漂浮导管不比颈内安全

C.当进入锁骨下静脉受阻时就应放弃

D.有静脉瓣，易受呼吸、头颈位置改变的影响

E.以上均是

肝性脑病病人昏迷期禁用

A．口服肠道抗生素
B．静滴高渗葡萄糖
C．生理盐水清洁灌肠
D．高蛋白、高维生素饮食
E．口服导泻剂

Do you know why different animals or pests have their special colours? Colours in them seem to be used mainly to protect themselves.

Some birds like eating locusts. but birds cannot easily catch them. Why? It is because locusts change their colours together with the change of the colours of crops. When crops are green, locusts look green. But as the harvest time comes, locusts change to the same brown colour as crops have. Some other pests with different colours from plants are easily found and eaten by others. So they have to hide themselves for lives and appear only at night.

If you study the animal life, you'll find the main use of colouring is protecting themselves. Bears, lions and other animals move quietly through forests. They cannot be seen by hunters. This is because they have the colours much like the tree.

Have you ever noticed an even more strange act? A kind of fish in the sea can send out a kind of very black liquid when it faces danger. While the liquid spread over, the enemies cannot find it. And it immediately swims away. So it has lived up to now though it isn't strong at all.

1. From the passage we learn that locusts ___ .

A. are small animals

B. are easily found by birds

C. are dangerous to their enemies

D. change their colours to protect themselves

2 How can pests with different colours from plants keep out of danger?

A. They run away quickly.

B. They colours much like their enemies.

C. They hide themselves in the day and appear at night.

D. They have to move quietly.

3. Bears and lions can keep safe because they ___ .

A. have the colours much like the trees   B. move quickly

C. like brown and grey colours         D. live in forests

4. Which is the best title for this passage?

A. The Change of Colours for Animals and Pests

B. Colours of Different Animals and Pests

C. The Main Use of Colours for Animals and Pests

D. Some Animals and Pests

我国工程设计采用以概率理论为基础、以分项系数表达得极限状态设计方法。（）