预膜是金属设备和管道表面保护层的一种类型，即是一种( )。A．物理转化膜 B．化学转

Dogs are generally called “man's best friend”. They are loyal, funny and loving. They seldom complain and always obey their owners. People who have dogs seem to be happier and healthier than those who live alone. One reason for this is that people with dogs lead more active lives. Who can say no to a lovely dog when he pulls on your arm and asks you to take him for a walk?

Dogs are really amazing animals. They not only provide great help for humans but also offer emotional support. Think about guide dogs for blind people, or dogs that help people in wheelchairs.

However, it is the emotional side of owning a dog that has been studied in detail by Dr Julie Davis of Chicago University. I have interviewed office workers and farmers, policemen and construction workers," says Dr Davis. Everyone wants to talk about their dogs. Many people said they cried much more when their dogs died than when their parents did. They said the sadness was much deeper. People tell me all the time that they get more emotional support from their dogs than they do from their husbands or wives."

小题1:What is the dog regarded as? (No more than 3 words)

小题2:Why do people with pet dogs seem happier and healthier than those having no dogs? (No more than 8 words)

小题3:Why does the writer think dogs are amazing animals? (No more than 11 words)

小题4:What can be concluded from Dr. Davis’ interview? (No more than 10 words)

在福莱特看来，群体过程的核心就是( )

A．创造

B．稳定

C．团结

D．摩擦

关于镇咳药的作用机制，下列叙述正确的是（）

A.抑制咳嗽反射弧中的感受器

B.抑制炎症介质的释放

C.抑制咳嗽反射弧中的传入神经纤维末梢

D.对抗过敏介质的作用

E.抑制延脑咳嗽中枢

【选修3-5选做题】

一个静止的，放出一个速度为v₁的粒子，同时产生一个新核，并释放出频率为υ的γ光子。写出该核反应方程式，求出这个核反应中产生的新核的速度v₂。（不计光子的动量）

（）是气焊、气割的主要任务。

A.触电

B.中毒

C.防火

D.防爆