如图所示,ABCD为匀强电场中相邻的四个等势面,一个电子垂直经过等势面D时动能为

题型:多选题

问题:

如图所示,ABCD为匀强电场中相邻的四个等势面,一个电子垂直经过等势面D时动能为20eV,经过等势面C时的电势能为-10eV,到达等势面B时速度恰好为零,已知相邻等势面间距离为5cm,则下列说法正确的是(  )

A.A等势面的电势为-10V

B.匀强电场的场强为200V/m

C.电子再次经过D等势面时,动能为l0eV

D.电子的运动是匀变速直线运动

考点:电势能等势面
题型:多选题

Amy usually ____________ at 8: 30 in the evening.[ ]

A. gets up

B. goes to bed

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( )是理解短期劳动需求曲线的中心概念,同时也是边际收益递减规律的主题。

A.劳动力的边际产量

B.劳动力的边际成本

C.劳动力的边际产量收益

D.劳动力的边际收益

题型:多选题

.

第二部分:阅读理解(共25小题,每题2分,满分50分)

第一节选择题(共20小题,每题2分,满分40分)

阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项。

Getting around in Canada is fairly easy. Most cities have urban transportation systems, including buses, streetcars, and trains, and some of the larger cities also have subways. You can board these systems at regular stops along their routes. Some let you pay with cash while others require tickets. If you don’t have a ticket for the bus, you must pay with the correct amount of money. This is because the driver does not carry any change. If you plan to stay in a city for a long time, you may want to buy a monthly pass or a package of tickets to save money. You can buy subway tickets at any subway station.

If you have to take several buses or subways for a single trip, you do not need to pay money each time. Simply ask the driver for a transfer (换乘) ticket, or take one from the machines on the subway platform.

If you are not sure where to board the bus or the streetcar, just ask someone or follow the crowd. People can usually only board at the front of the bus where you show your pass to the driver. When using public transportation, Canadians line up. First come, first serve, is a common approach to many activities in Canada, and it is considered to be extremely rude to cut in any line.

Maps of routes and schedules are usually available from the public transit (运输) company in your area, and there is also a telephone information line. You may ask someone for the name of the transit company in your area, and then look it up in the telephone book.

46. What is this passage mainly about?

A. How to use public transportation in Canada.

B. How to save money when traveling.

C. Where to find subways in larger cities.

D. How public transit companies work.

47. If you pay the bus fare in cash, _____.

A. you may be given some change

B. you can exchange money with the driver

C. it might cost you a little more

D. you must have the exact amount of money

48. By buying a monthly pass or a package of tickets, you can ______.

A. take a bus whenever you want      B. go wherever you like

C. save money                     D. find comfortable seats

49. If you have to change subway lines on a single trip, _____.

A. you have to pay each time

B. you should buy another ticket from the machine

C. you must ask for the driver’s permission

D. you just need to pay once

题型:多选题

哮喘急性发作常见的诱因是()

A.花粉

B.尘螨

C.感染

D.阿司匹林

E.剧烈运动

题型:多选题

旅游企业对投诉的应对措施是()

A.鼓励、方便投诉

B.主动征求消费者意见

C.鼓励员工灵活解决消费者面临的问题

D.提高旅游产品和服务的质量

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