假设有关系模式R = ， U = (A，B，C，D，E)，函数依赖集为F={A→BC

上市公司增发新股过程中的信息披露包括（）。

A.上市公告

B.路演公告

C.发行公告

D.招股意向书

Thomas Edison was born in America. He invented plenty of electric appliances(电器) and people from all over the world know him. At that time, there was no electric lamp in the world. And it brought people much trouble. Young Edison decided to invent it. He didn’t know which material was suited to be a lamp filament(灯丝). He failed and failed and he spent a lot of time on it. Some of his friends asked him to stop the experiments, but he didn’t listen to them and tried his best to find the material.

One afternoon, one of his friends came to visit him, he was doing his experiments in the lab when the man came in. But he only asked his friend to sit down and didn’t stop to talk with him. The man sat for a long time and Edison said nothing to him. His friend was angry with him and said, “You’ve done the experiments 1,200 times but you failed 1,200 times too!”

“You’re right, my friend,” Edison went on doing his experiments and said. “But I’ve known 1,200 materials are not suited to be a lamp filament!”

小题1:Why do many people know Edison?

A．Because he was very clever.

B．Because he worked hard.

C．Because he spent much time on his work.

D．Because he invented many electric appliances.小题2:He tried to find a kind of material which was suited to be ______.

A．a lamp

B．a lamp filament

C．a telephone

D．a light小题3: Edison was busy with his work, so ____________.

A．he asked his friend to help him

B．he asked his friend to go back first

C．he didn’t stop to talk with his friend

D．he asked his friend to watch him working小题4:His friend was angry because ____________.

A．he couldn’t persuade Edison to give up

B．Edison didn’t say hello to him

C．Edison failed 1,200 times

D．he didn’t think Edison was polite to him小题5:From the passage, we learn that ___________.

A．Edison was a hard-working person

B．Edison never gave up

C．Edison was rude to friends.

D．Both A and B

在一定的条件下，通过外界刺激即可使计算机病毒活跃起来，这种特性是计算机病毒的

A．破坏性

B．潜伏性

C．可传染性

D．可激发性

用一句话概括下面一段文字的内容，最恰当的一项是[ ]

　　我国目前从事专业文物修复的人才约400人，但馆藏文物已达1200万件，且有相当部分破损严重。按照妥善修复保存文物的要求，必须对所有文物进行定期轮修。如果依照国际通行的文物修复标准，以每位修复师每月修复一件文物计算，仅轮修一遍现有的1200万件馆藏文物就需要至少2500年时间。针对大量文物需要修复、修复力量又严重不足的情况，文物部门连年举办系列文物修复培训班以培养人才。但不断出土的大量文物却让这种修复仍显得遥遥无期。

A．不断出土的大量文物让修复显得遥遥无期

B．文物部门要多多举办培训班保证文物修复工作的进行

C．我国馆藏文物尚需2500年才能全部修复

D．从事文物修复人才的短缺影响了文物修复工作

农业节水要以（）为核心。

A.牧区节水改造

B.调整农业种植结构

C.提高灌溉水利用效率

D.建设高效输配水工程