下列数据中最符合实际的是()

【名词&注释】

传播速度(propagation velocity)、安全电压(safety voltage)、符合实际(conform to reality)、参差不齐(irregularity)、瞬息万变(illusive)

[单选题]下列数据中最符合实际的是()

A. 一节新干电池的电压为1．5 V
B. 今天教室内的气温约为60℃
C. 光在真空中的传播速度为340m/s
D. 对人体的安全电压为不高于220V

查看答案&解析查看所有试题

学习资料：

[单选题]C.Therehavebeenmanygreatinventionsorthingsthatchangedthewaywelive.Thefirstgreatinventionwastheone

A. thatisstillveryimportanttoday——thewheel.Thismadeiteasiertocarryheavythingsandtotravellongdistance.
B. Forhundredsofyearsafterthattherewerefewinventionsthatasmucheffectasthewheel.Thenintheearly1800
C. stheworldstartedtochange.Therewaslittleunknownlandleftintheworld.Peopledidn’thavetoexploremuchanymore.Theybegantoworkinsteadtomakelifebetter.
D. Inthesecondhalfofthe19thcenturymanygreatinventionsweremade.Amongthemwerethecamera,thelight
E. andtheradio.Theseallplayabigpartinourdailylifetoday.
F. Thefirstpartofthe20thcenturysawmoregreatinventions.Thehelicopterin1909,movieswithsoundin1926,the
G. computerin1928,jetplanesin1930.Thiswasalsoatimewhenanewmaterialwasfirstmade.Nyloncameoutin
H. 1935.Itchangedthekindofclothespeoplewore.
I. Themiddlepartofthe20thcenturybroughtnewwaystohelppeoplegetoverdiseases.Theyworkedverywell.They
J. madepeoplehealthierandallowedthemtolivelonger.Bythe1960smostpeoplecouldexpecttolivetobeatleast60.
K. Bythistimemostpeopleindevelopedcountrieshadaverygoodlife.Ofcoursenewinventionscontinuedtobemade.
L. Butmannowhadadesire(渴望)toexploreagain.Theearthwasknowntomanbutthestarswerenot.Manbeganlookingforwaystogointospace.
M. Russiamadethefirststep.ThenUnitedStatestookastep.Sincethenothercountries,includingChinaandJapan,
N. havemadetheirownstepsintospace.
O. In1969mantookhisbiggeststepawayfromearth.Americansfirstwalkedonthemoon.Thisiscertainlyjustabegin
P. ning,though.Newinventionswillsomedayallowustodothingswehaveneveryetdreamedof.
Q. 61.Thispassagetalksmainlyabout.
R. whycarswereveryimportant
S. whenlightwasinvented
T. howinventionsaffectpeople’sdailylife
U. whichcountrymadethefirststepintospace

[单选题]9．—What's her family name?—________.

A. It's 555806
B. Jim Green
C. Linda
D. Brown

[单选题]下列词语中，加点字的读音全部正确的一组是

A. 隽永（jùn） 煞费苦心（shà） 处境（chǔ） 参差不齐（chī）
B. 眩目（xuàn） 扣人心弦（xuán ） 湍急（cuān） 惴惴不安（zhuì）
C. 忐忑（tè） 截然不同（jié） 荤菜（hūn） 呱呱坠地（gūa）
D. 腼腆（diǎn ） 恬静优美（tián ） 吮吸（shǔn） 瞬息万变^(illusive)（shǔn）

本文链接：https://www.51ksbd.net/show/r470kv.html