问题 单项选择题

测定有孔材料(如普通砖)的密度时,应把材料按下列( )方法加工,干燥后用比重瓶测定其体积。

A.加工成比重瓶形状
B.磨成细粉
C.研碎成颗粒物
D.做成正方形

答案

参考答案:B

解析: 用比重瓶测定材料体积的方法称为排液法。测定有孔材料的密度时,须测定其密实状态下的体积,因此应将材料磨成细粉,消除材料颗粒内的孔隙,用排液法以便测得材料颗粒的密实体积。材料磨成的颗粒越粗,测得材料颗粒的密实体积越是不准确。

阅读理解

For most people, the word "fashion (时尚)" means "clothes". But people may ask the question, "What clothes are in fashion?" And they use the word "fashionable" in the same way.

"She was wearing a fashionable coat. His shirt was really a fashionable colour. "

But of course there are fashions in many things, not only in clothes. There are fashions in holidays, in restaurants, in films and books. There are even fashions in school subjects, jobs . . . and in languages.

Fashions change as time goes. If you look at pictures of people or things from the past, you will see that fashions have always changed. An English house of 1750 was different from one of 1650. A fashionable man in 1780 looked very different from his grandson in 1860.

Today fashions change very quickly. Some of this is natural. We hear about things much more quickly than in the past. Newspapers, radios, telephones and television send information from one country to another in a few hours.

New fashions mean that people will buy new things, so you see there is money in fashion.

小题1:Most people think that "fashion" means __________.

A.subjects

B.holidays

C.books

D.clothes小题2:By         we can see that fashions change as time goes.

A.finding a job

B.looking at pictures

C.eating in a restaurant

D.wearing a fashionable coat小题3:In the 5th paragraph , the writer mentions           kinds of ways to send information.

A.three

B.four

C.five

D.six小题4:"There is money in fashion" means      .

A.people like fashion and money

B.fashionable things are expensive

C.one can make money through fashion

D.a fashionable man makes much money小题5:The passage is mainly about             .

A.the changes of fashions

B.the kinds of colours

C.the money in fash ion

D.the differences between houses

多项选择题