下列计算正确的是 [ ] A.3a+3b=6ab B.3m﹣2n=1 C.2y+

题型:选择题

问题:

下列计算正确的是 [ ]

A.3a+3b=6ab

B.3m﹣2n=1

C.2y+5y+y=7y

D.﹣3a+3a=0

考点:整式的加减
题型:选择题

第二节(共5小题;每小题2分,共10分)

阅读下列短文,根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

(请将答案写在答题纸的指定区域内)

In many parts of the world, cars play an important role in daily life and many societies would not exist without them.   71  But this is the prediction made by a team of transport researchers who are taken seriously, not only by government but also by ear manufacturers.

The Human Science and Advanced Technology Institute at Loughborough in the UK is part of an international research program.   72  That will mean much saving, no accidents and better use of roads. The super-intelligent car of the 21st century will drive itself,   73 . Instead,we will have a choice of cars and change them as frequently as we change our clothing.

According to Dr.David Davis,who leads the research team,these predictions are based on the rising cost of the car culture,which had blocked up our cities,polluted our air, and caused more deaths than both world wars put together.

Davis says,cars will be fitted with some intelligent devices(装置) to regulate(调节) the distance between one car and another.   74  Computers are much safer drivers than people,so cars in a road train will be able to drive much closer together than cars driven by people.

By 2010,Dr.David Davis believes,car technology will give motorists a clear view of the road,whatever the weather conditions,by projecting an image(影像)of the road ahead on to the car’s windscreen.  75  Cars will be connected by an electronic tow bar to the car in front to form “road-trains”. “The front vehicle in such a train burns the normal amount.” says Davis. “ But all the others in the train would burn about ten percent of the normal amount,and so produce about ten percent of the pollution.”

A.The team there believes that by 2030 all cars will be computerized.

B.They believe that cars will become more important in 20 years.

C.And it will not be owned by one individual.

D.And by 2030, cars will travel in line, linked to each other electronically. E.So the idea that in 20 years’ time, no one will own cars may be hard to believe.

F.Every driver will use less fuel in the car he owns.

G.The car will automatically speed up, or slow down, to match the speed of the car in front.

题型:选择题

《中华人民共和国环境影响评价法》规定:建设项目建设过程中,建设单位应当同时实施( )中提出的环境保护对策措施。

A.环境影响登记表以及审批部门审批意见
B.环境影响报告书、环境影响报告表以及环境影响评价文件审批部门审批意见
C.环境影响报告书及审批部门审批意见
D.环境影响报告表及审批部门审批意见

题型:选择题

工件装夹包括定位和夹紧两个过程。( )

题型:选择题

某建筑公司承建市政府办公楼,工程不含税造价为3200万元,则该施工企业应缴纳城市维护建设税为( )万元。

A.6.95

B.4.96

C.2.98

D.11.58

题型:选择题

在零件图的标题栏中,可以查看到零件的()等信息。

A.用途

B.名称

C.代号

D.材质

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