数控系统常见的插补方法有（）。 A.偏差判别法 B.终点判别法 C.时间分割法 D.

男性患者，53岁。有酗酒史，3小时前进餐后突然出现剧烈上腹痛。查体：BP110/70mmHg，P116次／分，巩膜无黄染，全腹压痛，伴反跳痛和肌紧张，移动性浊音（-），肠鸣音4次／分。血淀粉酶210U/L。腹部平片：未见膈下游离气体。腹部超声：肝胆脾胰腺未见异常。下列诊断可能性最大的是（）。

A.急性重症胰腺炎

B.绞窄性肠梗阻

C.急性胆囊炎

D.十二指肠溃疡穿孔

E.急性心肌梗死

“菌落”是指（）

A.不同种的细菌在培养基上生长繁殖而形成肉眼可见的细菌集团

B.细菌在培养基上生长繁殖而形成肉眼可见的细菌集团

C.单个细菌在培养基上生长繁殖而形成肉眼可见的细菌集团

D.单个细菌

E.从培养基上脱落的细菌

下表列出了实验测定的几种物质的密度．

几种物质的密度（常温常压下，单位：kg/m³．）

铜	8.9×103	水银	13.6×103	氧气	1.43
铁	7.9×103	纯水	1.0×103	空气	1.29
铝	2.7×103	煤油	0.8×103	水蒸气	0.60
冰	0.9×103	酒精	0.8×103	氢气	0.09

认真阅读上表，你一定能有所发现，请写出任意三条发现：______、______、______．

遗传性球形红细胞增多症末梢血中的球形红细胞可占红细胞的百分比是多少（）

A．＞10%

B．＞80%

C．＞40～60%

D．60%～80%

E．20%～40%

Time spent in a bookshop can be most enjoyable, whether you are a book-lover or merely there to buy a book as a present. You may even have entered the shop just to find shelter from a sudden shower. But the desire to pick up a book with an attractive dust-jacket is irresistible. You soon become absorbed in some book or other, and usually it is only much later that you realize that you have spent far too much time there.

This opportunity to escape the realities of everyday life is, I think, the main attraction of a bookshop. There are not many places where it is possible to do this. A music shop is very much like a bookshop. You can wander round such places to your heart’s content. If it is a good shop, no assistant will approach you with the inevitable greeting: "Can I help you, sir" You needn’t buy anything you don’t want. In a bookshop an assistant should remain in the background until you have finished browsing. Then, and only then, are his services necessary.

You have to be careful not to be attracted by the variety of books in a bookshop. It is very easy to enter the shop looking for a book on, say, ancient coins and to come out carrying a copy of the latest best-selling novel and perhaps a book about brass-rubbing -- something which had only vaguely interested you up till then. This volume on the subject, however, happened to be so well illustrated and the part of the text you read proved so interesting that you just had to buy it. This sort of thing can be very dangerous. Booksellers must be both long suffering and indulgent.

There is a story which wei1 illustrates this. A medical student had to read a textbook which was far too expensive for him to buy. He couldn’t obtain it from the library and the only copy he could find was in his bookshop. Every afternoon, therefore, he would go along to the shop and read a little of the book at a time. One day, however, he was dismayed to find the book missing from its usual place and about to leave when he noticed the owner of the shop beckoning to him. Expecting to be reproached, he went toward him. To his surprise, the owner pointed to the book, which was tucked away in a corner. "I put it there in case anyone was tempted to buy it," he said, and left the delighted student to continue his reading.

According to the text, in a good bookshop（）

A. nobody takes any notice of you

B. the assistant greets you in a friendly way

C. your heart is contented

D. you feel that you are in a music shop