下列关于氧气的化学性质的说法正确的是[ ] A ．比较活泼，在加热的条件下能跟许

E–book is short for electronic(电子) book. It is usually read on personal computers. Some mobile phones can also be used to read e–books.

Earlier e–books were written for a certain group of readers and were about only a few subjects. With the development of the Internet, knowledge and answers to a lot of questions mainly come from e–books. This is why the e–book business is increasing quickly.

E–books have many advantages. First, they save time. We don’t need to go a bookstore to buy books. Besides, we can find the topic we want to know about on the Internet, and then we can quickly get many e–books on similar topics. Second, e–books save money. Some e–books cost us little money, and there are millions of e–books on the Internet that we can get for free. Third, more trees are saved because e–books don’t need to be printed on paper. Fourth, e–books make reading more convenient. You can carry a whole library of hundreds of books with you in a small computer or any e–book reader(阅读器), without worrying about their weight.

But e–books have certain disadvantages. They need a personal computer or an e–book reader, and the information can be lost if its file format(文件格式) is not supported(支持) or changed in the reader’s computer.

However, e–books provide us with a new way of reading. That is good.

小题1:Why is the e–book business increasing quickly? Because______________.

A．earlier e–books are about only a few subjects.

B．people don’t like to read any paper books any more.

C．the development of the Internet makes e–books more useful.

D．most e–books have been written for a certain group of readers.小题2:How many advantages do e–books have according to this article?

A．Three.

B．Four.

C．Five

D．Six小题3:Which of the following is TRUE according to this article?

A．All the e–books on the Internet cost lots of money.

B．E–books can’t be read on mobile phones.

C．You can’t read e–books without a personal computer.

D．E–books can make reading more convenient.小题4:What is the disadvantage of the e–books?

A．You’ll lose the information if its file format is not supported.

B．You can read e–books any time.

C．You can buy cheap e–books anywhere.

D．You can carry hundreds of books in an e–book reader.小题5:The writer mainly tells us _________.

A．the information can be lost if its file format is changed.

B．you don’t need to buy paper books in a bookstore if you read e–books.

C．the development of e–books can help save the environment.

D．e–books affor（提供） us a new good way of reading.

首创小儿五脏证治法则的著作是《颅囟经》。

借贷记账法下，期末一般有余额的是（）。

A.资产类账户

B.权益类账户

C.收入类账户

D.费用类账户

科学家把猪、牛、羊、马一起放在施放了有毒氯气的自然环境中做试验，它们中谁逃脱了厄运( )

A．猪
B．牛
C．羊
D．马

常用的消毒剂不包括

A． 高锰酸钾

B．石碳酸

C． 甲醇

D．碘酒

E．环氧乙烷