宏观调控手段系统是由税收杠杆、信贷杠杆、外汇杠杆、价格杠杆组成的。 ( )

题型:判断题

问题:

宏观调控手段系统是由税收杠杆、信贷杠杆、外汇杠杆、价格杠杆组成的。 ( )

考点:地方公务员公共基础知识重庆公务员
题型:判断题

暗能量与宇宙

宇宙至少还能再活300亿年左右。美国科学家里斯于2004年2月公布这一研究结果时,将其称为一个“好消息”。美国太空望远镜科学研究所的里斯等科学家说,他们首次对宇宙中暗能量的持久性进行了富有意义的测量,并得到上述结论。里斯等人的研究显示,暗能量的特性似乎不会随着时间的推移而发生变化,这意味着宇宙可能会永远膨胀下去,而不是像一些科学家所预言的那样会走向“大分裂”和“大坍塌”。

上世纪20年代,埃德温·哈勃发现宇宙并非静止而是在膨胀。1998年,科学家施密特通过超新星观测到宇宙在加速膨胀,他们用暗能量来解释这一现象。暗能量据认为可以产生与引力相反的排斥力。2003年7月23日,美国匹兹堡大学瑞安·斯克兰顿博士领导的一个多国科学家小组宣称,发现宇宙暗能量存在的证据。观测还发现近73%的宇宙由暗能量组成,这种奇特的力量似乎正在使宇宙加速膨胀。

目前,关于暗能量的来源主要有两种理论。一种观点认为,暗能量类似爱因斯坦曾在广义相对论中引入能产生排斥力的“宇宙常数”,是一种从真空中弥漫出来的能量,不会随着时间改变,强度固定。但也有科学家提出,暗能量与一种变化的动态能量场相关,能量场导致目前宇宙加速膨胀。按照暗能量稳定存在的假设,宇宙将会永远加速膨胀下去。而如果暗能量本身不稳定,那么宇宙有可能迎来动荡的末日。比如有科学家认为,如果暗能量的排斥力超出爱因斯坦的预测,那么宇宙可能最终会走向“大分裂”,所有物质将在宇宙的急剧膨胀中被撕裂。还有科学家预言,如果暗能量是可变的,那么暗能量也许有一天会突然发生跳转,由排斥变成将膨胀的宇宙往回拉,宇宙最后将在向心挤压下产生“大坍塌”。

里斯等人利用“哈勃”太空望远镜寻找到42颗超新星,对它们进行观测,以研究宇宙在过去不同历史时期的膨胀速率。研究结果显示,暗能量似乎更接近爱因斯坦的理论预测:即使暗能量产生变化,速度也不会很快。里斯称,新观测结果使他们对爱因斯坦“宇宙常数”正确性的信心倍增。

科学家们指出,根据他们研究的新结果,即使爱因斯坦的理论是错误的,最起码在今后300亿年中,暗能量的变化不会导致宇宙毁灭。不过他们也强调说,要想加深对暗能量的理解和确定宇宙的最终命运,尚需要进行更多的观测。

小题1:下列对“宇宙膨胀”的解释,正确的一项是

A.里斯认为暗能量的特性几乎是固定不变的,必将导致宇宙永远膨胀下去。

B.埃德温·哈勃认为宇宙并非静止不动,而是在不断地膨胀。

C.施密特认为宇宙加速膨胀是暗能量可以产生与地球引力相反的排斥力所致。

D.瑞安·斯克兰顿认为宇宙约有73%由暗能量组成,并且使宇宙加速膨胀。小题2:从全文来看,下列不属于里斯的研究成果的一项是

A.宇宙至少还能再活300亿年。

B.宇宙不会走向“大分裂”或“大坍塌”。

C.如果暗能量产生变化,速度也不会很快。

D.暗能量本身不稳定,宇宙有可能迎来动荡末日。小题3:根据本文提供的信息,下列推断正确的一项是

A.里斯首次对宇宙暗能量的持久性进行测量,并最终确定宇宙还能再活300亿年。

B.如果物质在宇宙的急速膨胀中有的发生撕裂,那么宇宙最终会走向灭亡。

C.科学家认为,如果暗能量是可变的,那么地球也许有一天会突然发生跳转。

D.科学家强调说,只有细致的观察深入地研究,才能加强对暗能量的理解和确定宇宙的最终寿命。

题型:判断题

若血色素化验的准确率是p, 则在10次化验中,有两次不准的概率   

题型:判断题

JANE AUSTEN(1775—1817)is often regarded as the greatest of English women novelists on the strength of her six completed novels.Known particularly for their social comedy and accurate description of human relationships,they are still as widely read today as they have ever been.

The seventh child of a country priest(牧师),Jane Austen was born on 16 December 1775 at Steventon in Hampshire.Her father ,the Reverend George Austen,was an intelligent and sensitive man who encouraged Jane in her love of reading.From an early age she was familiar with the works of Henry Fielding,Sir Walter Scott,Richardson,Frances Burney and the poet George Crabbe.Her early attempts at writing include burlesques(滑稽作品)of popular romances.When her father retired in 1801 the family moved to Bath,which was later to feature in her novel Northanger Abbey(published in 1818).After his death in 1805 the family moved first to Southampton and then in 1809 to Chawton in Hampshire.where Jane Austen is known to have written her last three novels:Mansfield Park(1814),Emma(1816)and Persuasion(also published in 1818).Although her other novels were written much earlier ,it was not until 1811 that Sense and Sensibility was first published.Pride and Prejudice,which followed in1813,features Jane Austen’own favourite hero,Elizabeth Bennet.

Surrounded by her lively and warm family and wholly buried herself in her writing and housework,Jane Austen led a life often known for its lack of events.She did,however ,attract several admirers and even accepted a proposal of marriage from one admirer-only to change her mind the following morning.Jane Austen’s independent life often seems reflected in her novels,which seem to display the world in miniature(缩影).Sir Walter Scott praised Jane Austen for‘that unique touch which makes ordinary commonplace things and characters interesting’,while Somerset Maugham claimed that she had at her command ‘the most precious gift a novelist can possess’s that of keeping the reader’s interest.Jane Austen died in 1817.

小题1:The underlined word“touch” in the third paragraph is closest in meaning to      

A.style

B.contact

C.taste

D.attitude小题2:Which of Jane Austen’s novels were published after her death?

A.Northanger Abbey and Mansfield Park.

B.Northanger Abbey and Persuasion.

C.Pride and Prejudice and Emma.

D.Sense and Sensibility and Persuasion.小题3:We can infer from the passage that Jane Austen had a gift for     

A.attracting admirers

B.reflecting her own life in all her novels

C.making dull things and characters interesting

D.holding the readers’ interest小题4:This passage is most probably a      

A.collection of women novelists and their works

B.comment on Jane Austen and her works

C.brief introduction of Jane Austen

D.description of Jane Austen’s road to success

题型:判断题

治疗瘙瘕痰湿证,应首选

A.开郁二陈汤
B.苍附导痰丸
C.香棱丸
D.桂枝茯苓丸
E.血府逐瘀汤

题型:判断题

关于BitTorrent的描述中,正确的是()

A.是最早的P2P文件共享系统

B.Tracker服务器存放用户信息

C.Tracker服务器存储下载文件

D.用户数越多,下载速度越慢

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