不能用质量守恒定律解释的现象是( ) A.潮湿的衣服在阳光下晒干 B.蜡烛燃烧后

题型:选择题

问题:

不能用质量守恒定律解释的现象是(  )

A.潮湿的衣服在阳光下晒干

B.蜡烛燃烧后,越来越短,最终消失

C.铁丝燃烧,固体的总质量增加

D.碱式碳酸铜受热,固体的总质量减少

考点:质量守恒定律
题型:选择题

甲、乙签订一份购销合同,甲将自己取得的银行承兑汇票背书转让给乙,以支付货款。甲在汇票的背书栏记载有“若乙不按期履行交货义务,则不享有票据权利”,乙又将此汇票背书转让给丙。根据票据法律制度的规定,下列表述中,正确的有( )。

A.该票据的背书行为为附条件背书,背书的效力待定

B.乙在未履行交货义务时,不得主张票据权利

C.无论乙是否履行交货义务,票据背书转让后,丙取得票据权利

D.背书所附条件不产生汇票上的效力,乙无论交货与否均享有票据权利

题型:选择题

已知某船在静水中的速率为4m/s,现让船渡过某条河,假设这条河的两岸是理想的平行线,河宽为100米,河水的流动速率为5m/s,方向与河岸平行,则

A.船不能垂直河岸渡河

B.欲使船渡河的航程最短,船头应指向斜向上游,与河岸成角,

C.船渡河的最短航程是125米

D.船能垂直河岸渡河,最短航程是100米

题型:选择题

Imagine,one day,getting out of bed in Beijing and being at your office in Shanghai in only a couple of hours,and then,after a full day of work,going back home to Beijing and having dinner there.

Sounds unusual,doesn't it? But it's not that unrealistic,with the development of China’s high—speed railway system.And that’s not a11.China has an even greater high—speed railway plan—to connect the country with Southeast Asia,and eventually Eastern Europe.

China is negotiating to extend its own high·-speed railway network to up to 17 countries in 1 0 to 15 years,eventually reaching London and Singapore.

China has proposed three such projects.The first would possibly connect Kunming withSingapore via Vietnam and Malaysia.Another could start in Urumqi and go through Kazakhstan and Uzbekistan,and possibly

to Germany.The third would start in the northeast and go north through Russia and then into Western Europe.

If China’s plan for the high-speed railway goes forward,people could zip over from London to Beiling in under two days.

The new system would still follow China’s high—speed railway standard.And the trains would be able to go 346 kilometers an hour,almost as fast as some airplanes.

China’s bullet train(高速客车),the one connecting Wuhan to Guangzhou,already has the

World’s fastest average speed.It covers 1,069 kilometers in about three hours.

Of course,there are some technical challenges to overcome.There are so many issues that need to be settled,such as safety,rail gauge(轨距),maintenance of railway tracks.So,it’s important to pay attention to every detail.

But the key issue is really money.China is already spending hundreds of billions of yuan on

domestic railway expansion.

China prefers that the other countries pay in natural resources rather than with capital

investment.Resources from those countries could stream into China to sustain development.

It’11 be a win-win project. For other countries,the railway network will definitely create more opportunities for business,tourism and so on,not to mention the better communication among those countnes.

For China,such a project would not only connect it with the rest of Asia and bring some much-needed resources,but would also help develop China’s far west.We foresee that in the coming decades,millions of people will migrate to the western regions,where the land is empty and resources unused.With high-speed trains,people will set up factories and business centers in the west once and for a11.And they’11 trade with Central Asian and Eastern European countries.

1.China’s new high-speed railway plan will be a win-win project because ____________.

A.China will get much-needed resources and develop its western regions

B.China and the countries involved will benefit from the project in various ways

C.China will develop its railway system and communication with other countries

D. the foreign countries involved will develop their railway transportation,business and tourism

2.According to the passage,the greatest challenge to the new high-speed railway plan is____________.

A.technical issues    B.safety of the system

C.financial problems  D.maintenance of railway tracks

3.Which of the following words best describes the author’s attitude towards China’s high-speed

railway plan?

A.Critical.    B.Reserved.    C.Doubtful     D. Positive.

4.Which of the following might be the best title for the passage?

A.New Railway Standards    B.Big Railway Dreams

C.High—speed Bullet Trains D.International Railway Network

题型:选择题

以下量数为无单位量数的是( )。

A.

B.M

C.CV

D.AD

题型:选择题

在InDesign中定义一个专色,如果需要套印的话,该如何设置?

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