1865 年德国化学家凯库勒提出 , 苯是一个 () 六元碳环 , 环上碳原子之间以单双键交替排列。

A、平面
B、带支链
C、立体
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正确答案:

A

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Californiaisalandofvarietyandcontrast.Almosteverytypeofphysicallandfeature,sortofarcticicefieldsandtropicaljunglescanbefoundwithinitsborders.Sharplycontrastingtypesoflandoftenlieveryclosetooneanother.PeoplelivinginBakersfield,forinstance,canvisitthePacificOceanandthecoastalplain,thefertileSanJoaquinValley,thearidMojaveDesert,andthehighSierraNevada,allwithinaradiusofabout100miles.Inotherareasitispossibletogosnowskiinginthemorningandsurfingintheeveningofthesameday,withouthavingtotravellongdistance.ContrastaboundsinCalifornia.ThehighestpointintheUnitedStates(outsideAlaska)isinCalifornia,andsoisthelowestpoint(includingAlaska)。MountWhitney,14,494feetabovesealevel,isseparatedfromDeathValley,282feetbelowsealevel,byadistanceofonly100miles.Thetwoareashaveadifferenceinaltitudeofalmostthreemiles.Californiahasdeep,clearmountainlakeslikeLakeTahoe,thedeepestinthecountry,butitalsohasshallow,saltydesertlakes.IthasLakeTulainyo,12,020feetabovesealevel,andthelowestlakeinthecountry,theSaltonSea,236feetbelowsealevel.Someofitslakes,likeOwensLakeinDeathValley,arenotlakesatall:theyaredrieduplakebeds.Inadditiontomountains,lakes,valleys,deserts,andplateaus,CaliforniahasitsPacificcoastline,stretchinglongerthanthecoastlinesofOregonandWashingtoncombined.

1.WhichofthefollowingisthelowestpointintheUnitedStates?

A.LakeTulainyoB.MojavedesertC.DeathValleyD.TheSaltonSea

2.WhereisthehighestpointintheUnitedStateslocated?

A.LakeTahoe.

B.SierraNevada.C.MountWhitney.

D.Alaska.

3.HowfarawayisDeathValleyfromMountWhitney?

A.About3miles.

D.14,494feet.

4.WhichofthefollowingisNOTmentionedinthepassageasbeingwithinaradiusofabout100milesofBakersfield?

A.ThePacificOcean.

B.SanJoaquinValley.

C.MojaveDesert.

D.OregonandWashington.

5.WhichstatementbestdemonstratesthatCaliforniaisalandofvarietyandcontrast?

A.ThehighestlakeinCaliforniaisLakeTulainyo.

B.ItispossibletogosurfingandsnowskiinginsomepartsofCaliforniawithouthavingtotravellongdistance.

C.SierraNevada,SanJoaquinValley,MojaveDesertandthePacificOceanallliewithinaradiusofabout100miles.

D.OwensLake,inDeathValley,isnotreallyalakeatall.

翻译:

邓小平同志曾说:“社会主义财富属于人民,社会主义的致富是全民共同致富。”构建和谐社会,就是要把民生问题作为重中之重,让广大人民群众有活干,有学上,有饭吃,有衣穿,有屋住,病有医,老有养,生活幸福,都过上好日子。自此,在就业、教育、收入分配、医疗、养老、住房等领域,一大批关注民生的实事工程接连开工,一件件事关百姓冷暖的民生大事让各族群众喜笑颜开。

Modern____perhapscausesmoreproblemsthanitsolves.

A、technique
B、technology
C、tactics
D、tendency

Ifnot_____withtherespecthefeelsduetohim,Jackgetsveryill-temperedandgrumblesallthetime.

A、beingtreated
B、treated
C、betreated
D、havingbeentreated

TheClarkshaven’tdecidedyetwhichhotel_____.

A、tostay
B、istostay
C、tostayat
D、isforstaying
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