在光滑的水平面上有一物体,它的左端连接有一弹簧,弹簧的另一端固定在墙上,在力F作

题型:选择题

问题:

在光滑的水平面上有一物体,它的左端连接有一弹簧,弹簧的另一端固定在墙上,在力F作用下物体处于静止状态,当撤去F后,物体将向右运动,在物体向右运动的过程中下列说法正确的是

A.弹簧的弹性势能逐渐减小

B.弹簧的弹性势能逐渐增大

C.弹簧的弹性势能先增大再减小

D.弹簧的弹性势能先减小再增大

考点:功能关系
题型:选择题
迭择合适的介词填空。
   to   at   for   in   of   from   on   about
1. Mary is good _______ drawing.
2. I've got an email ______ English. It's _______ my friend.
3. Lingling is _______ the phone for Daming.
4. Are you ready _______ your trip _______ America?
5. How _______ chopsticks?
6. What kind ________ computer did you buy?
题型:选择题

材料l 我们党要始终代表中国先进生产力的发展要求,就要党的理论,路线,纲领,方针,政策和各项工作必须努力符合生产力的发展的规律,体现不断推动社会生产力的解放和发展的要求,尤其要体现推动先进生产力发展的要求,通过发展生产力不断提高人民群众的生活水平. 材料2 我们党要始终代表中国先进文化的前进方向,就是党的理论,路线,纲领,方针,政策和各项工作必须努力体现发展面向现代化,面向世界,面向未来的民族的科学的大众的社会主义文化的要求,促进全民族思想道德素质和科学文化素质的不断提高,为我国经济发展和社会进步提供精神动力和智力支持. 请回答下列问题

运用所学的经济常识知识谈谈你对材料一的认识.

题型:选择题

阅读理解。

     The year is 2094. It has been announced that a comet(彗星) is heading towards the

earth. Most of it will miss our planet, but two pieces will probably hit the southern half

of the earth.

     On 17 July, a piece four kilometers wide enters the earth's atmosphere(大气层) with a

massive explosion. About half of the piece is destroyed, but the remaining part hits the

South Atlantic at 200 times the speed of sound. The sea boils and a huge hole is made in

the sea bed. Huge waves are created and spread outwards from the hole. The wall of water,

a kilometer high, rushes towards southern Africa at 800 kilometers an hour. Cities on the

African coast are totally destroyed and millions of people are drowned.

     Before the waves reach South America, the second piece of the comet lands in

Argentina. Earthquakes and volcanoes are set off in the Andes Mountains. The shock

waves move north into Califomia and all around the Pacific Ocean. The cities of Los

Angeles, San Francisco and Tokyo are completely destroyed by earthquakes. Millions

of people in the southern half of the earth are already dead, but the north won't escape

for long. Because of the explosions, the sun is hidden by clouds of dust, temperatures

around the world fall to almost zero.Crops are ruined. The sun won't be seen again for

many years. Wars break out as countries fight for food. A year later, no more than 10

million people remain alive.

     Could it really happen? In fact, it has already happened more than once in the history

of the Earth. The dinosaurs were on the Earth for over 160 million years. Then 65 million

years ago they suddenly disappeared. Many scientists believe that the Earth was hit by

a piece of object in space. The dinosaurs couldn't live through the cold climate that

followed and died out. Will we meet the same end?

1. What is mainly described in the passage?______

A. A historic discovery.

B. An event of imagination.

C. A research on space.

D. A scientific adventure.

2. When the first piece hits the South Atlantic, it causes.______

A. an earthquake

B. damages to cities

C. an Earth explosion

D. huge waves

3. Why can't the northern half of the Earth escape for long?______

A. Because the land is covered with water.

B. Because the light and heat from the sun can not reach the earth.

C. Because people there can not live at the temperature of zero.

D. Because wars break out among countries.

4. By giving the example of dinosaurs, the author tries to prove .______

A. animals could not live in the cold climate

B.what happened 65 million years ago was an invented story

C. the human beings will die out in 2094

D. the Earth could be hit by other objects in space

题型:选择题

下列不属于结算种类的是()。

A、存折

B、银行本票

C、银行汇票

D、商业汇票

题型:选择题

回顾你们公司的旧信息系统上的教训,你终于说服了管理层从项目开始时就进行系统的可维护性设计。但是不管对项目设计进行怎样的考虑()

A.系统运行维护应该总是在项目结束阶段被考虑的活动

B.对信息系统项目的生命期应该有一个独立的系统维护阶段,因为60%~70%的计算机系统生命期的成本通常被用于维护

C.系统运行维护不能被视为项目生命期的一部分

D.系统运行维护不应被视为独立的项目

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