美国全国公共关系协会(PRSA)成立的时间是( )A．1978年 B．1955年

运算级别最高的运算符是（）。

A.算术

B.关系

C.逻辑

D.字符

It was Monday,Mrs Smith’s dog was hungry,but there was not any meat in the house.

Considering that there was no better way,Mrs Smith took a piece of paper,and wrote the following words on it:”Give my dog half a pound of meat.” Then she gave the paper to her dog and said gently:”Take this paper to the butcher（卖肉者）,and he is going to give you your lunch today.”

Holding the piece of paper in its mouth,the dog ran to the butcher’s shop.It gave the paper to the butcher.The butcher read it carefully ,he was sure that it was really the lady’s handwriting and presently did as he was asked to.The dog was very happy,and ate the meat up immediately.

At midnight the dog came to the shop again.It gave the butcher a piece of paper again.After reading it ,he gave it half a pound of meat once more.

The next day the dog came again exactly at midday.And as usual it brought a piece of paper in the mouth.This time the butcher did not take a look at the paper,and gave the dog its meat,for he had regarded the dog as one of his customers.

But the dog came again at four o’clock.And the same thing happened once again.To the butcher’s more surprise ,it came for the third time at six o’clock,and brought with it a third piece of paper.The butcher felt a bit puzzled.He said to himself,”This is a small dog.Why does Mrs. Smith give it so much meat to eat today?”

Looking at the piece of paper,he found that there were not any words on it!

小题1:It seemed that the dog knew well that the paper its master gave it______.

A．might do it much harm

B．could do it much good

C．would give the butcher some meat

D．was worth many pounds小题2:The butcher did not give any meat to the dog______.

A．when he found the words on the paper were not very clear

B．because he happened to have sold out all the meat in his shop

C．until he was paid enough by Mrs Smith

D．before he felt sure that the words were really written by Mrs Smith小题3:From its experience,the dog found that______.

A．a piece of paper could bring him half a pound of meat

B．only the paper from Mrs Smith’s words on it could bring it meat

C．the butcher would give it meat whenever he saw it

D．Mrs Smith would pay for the meat it got from the butcher小题4:At the end of the story you’ll find that______.

A．the dog was clever enough to write on the paper

B．the butcher found himself cheated by the smart animal

C．the dog dared not go to the butcher’s any more

D．the butcher was told not to give any meat to the dog

下列关于气雾剂特点的叙述，错误的是（）

A.奏效迅速

B.定位作用

C.给药剂量准确、副作用小

D.生产成本低

E.使用方便

致脓液为粘稠、黄色、无臭的病原菌是（）

A．葡萄球菌

B．链球菌

C．大肠杆菌

D．绿脓杆菌

E．变形杆菌

什么是监控摄像机的峰值感应模式？