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關於19B.25C.31D.30的百科

設x1,x2是方程x2+5x﹣3=0的兩個根,則x12+x22的值是(  ) A.19B.25C.31D.30...
計算:30=
  • 計算:30=

  • 問題詳情:計算:30=______;=______.【回答】1 【解析】;故*為:1;.知識點:分式的運算題型:填空題...
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It’s8:30,timeforJohntostartwork.Soheturnsonhisradio.The...
  • It’s8:30,timeforJohntostartwork.Soheturnsonhisradio.The...

  • 問題詳情:It’s8:30,timeforJohntostartwork.Soheturnsonhisradio.Thenheeatsbreakfast.Asheeats,hereadshise-mailandreviewshisto-dolist.Thenhesitsonthesofaandthinksaboutanarticleheneedstowrite...Waitaminute!Radio?Breakfast?Sofa?Whatkindofworkplaceisthis?Wel...
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在△ABC中,∠C=30°,∠A﹣∠B=30°,則∠A=    .
用*法解方程x2﹣4x﹣3=0,下列*結果正確的是(    )     A.(x﹣4)2=19B.(x﹣2...
如圖,△ABC≌△AED,∠C=40°,∠EAC=30°,∠B=30°,則∠D=   ,∠EAD=     .
原產量n噸,增產30%之後的產量應為(      )A、(1-30%)n噸        B、(1+30%)n...
Pleasecallagainat10:30,
  • Pleasecallagainat10:30,

  • 問題詳情:Pleasecallagainat10:30,__________timethemeetingshouldbeover.A.towhich      B.bywhich               C.fromwhich       D.ofwhich 【回答】 B知識點:定語從句題型:選擇題...
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錳元素的相關資訊如圖所示.下列說法中正確的是A.屬於金屬元素B.原子核內中子數為25C.原子的核外電子數為30...
 —Canyougetmetothestationby11:30?—
  •  —Canyougetmetothestationby11:30?—

  • 問題詳情: —Canyougetmetothestationby11:30?—_______.It’sonly10o’clocknow.A.Goodidea              B.I’mwithyou           C.Notexactly              D.Noproblem【回答】D知識點:交際用語題型:選擇題...
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中緯度是指(   )A.30°-60° B.23.5°-66.5°      C.0°-30°        ...
已知:25C時,Ksp[Zn(OH)2]=1.0×10-18,Ka(HCOOH)=1.0×10-4。該溫度下,...
  • 已知:25C時,Ksp[Zn(OH)2]=1.0×10-18,Ka(HCOOH)=1.0×10-4。該溫度下,...

  • 問題詳情:已知:25C時,Ksp[Zn(OH)2]=1.0×10-18,Ka(HCOOH)=1.0×10-4。該溫度下,下列說法錯誤的是(   )A.HCOO-的水解平衡常數為1.0×10-10B.向Zn(OH)2懸濁液中加少量HCOOH,溶液中c(Zn2+)增大C.Zn(OH)2溶於水形成的飽和溶液中,c(Zn2+)>1.0×10-6mol/LD.Zn(OH)2(s)+2HCOOH(aq)...
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人體每天早、中、晚三餐的能量攝入比例正確的是(  )A.30%:40%:30%   B.40%:30%:30%...
JoannewasstuckinatrafficjamincentralBirminghamat5:30.an...
  • JoannewasstuckinatrafficjamincentralBirminghamat5:30.an...

  • 問題詳情:JoannewasstuckinatrafficjamincentralBirminghamat5:30.andat6:30shewasexpectedtobechairingameetingofthetennisclub.Atlast,thetrafficwasmoving.SheswungquicklyracingtoherhouseAssheopenedthedoor,shenearlytrippedoverSheba.      “Hey,Sheba,”shesaid,“I...
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      Signsof“BusOnly,7:00-9:00,16:30-18:30”arepaintedi...
  •       Signsof“BusOnly,7:00-9:00,16:30-18:30”arepaintedi...

  • 問題詳情:      Signsof“BusOnly,7:00-9:00,16:30-18:30”arepaintedinwhitetopreventvehiclesfromusingthebus_______duringrushhourseveryday.      A.lanes         B.pavement          C.system           D.station【回...
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圖中P點的經緯度是(    )A.30°、30°    B.30°E、30°S  C.30°W、30°N   ...
已知等差數列{an}的前n項和為Sn,且S10=12,S20=17,則S30為A.30B.25C.20D.15
  • 已知等差數列{an}的前n項和為Sn,且S10=12,S20=17,則S30為A.30B.25C.20D.15

  • 問題詳情:已知等差數列{an}的前n項和為Sn,且S10=12,S20=17,則S30為A.30B.25C.20D.15【回答】.D【解析】因為Sn是等差數列{an}的前n項和,所以S10,S20-S10,S30-S20成等差數列,所以S10+(S30-S20)=2(S20-S10),所以12+(S30-17)=2×(17-12),解得S30=15.【備註】無知識點:數列題型...
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等比數列{an}中,a5a14=5,則a8a9a10a11=(  ) A.10B.25C.50D.75
  • 等比數列{an}中,a5a14=5,則a8a9a10a11=(  ) A.10B.25C.50D.75

  • 問題詳情:等比數列{an}中,a5a14=5,則a8a9a10a11=()A.10B.25C.50D.75【回答】考點:等比數列的*質.專題:計算題.分析:由等比數列的通項公式的*質知a8a9a10a11=(a5a14)2,由此利用a5a14=5,能求出a8a9a10a11的值.解答:解:∵等比數列{an}中,a5a14=5,∴a8a9a10a11=(a5a14)2=25.故選B.點評:本題考查等比數列的...
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.已知△ABC中,a=4,b=4,∠A=30°,則∠B等於( )A.30°    B.30°或150°    ...
(﹣﹣)×(﹣30)
  • (﹣﹣)×(﹣30)

  • 問題詳情:(﹣﹣)×(﹣30)【回答】原式=×(﹣30)﹣×(﹣30)﹣×(﹣30)=﹣25+15+18=8;知識點:有理數的乘除法題型:計算題...
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 A:Whattimedoyougetup?B:At6:30
  •  A:Whattimedoyougetup?B:At6:30

  • 問題詳情: A:Whattimedoyougetup?B:At6:30________.A.intheafternoon    B.inthemorning   C.atnight 【回答】B知識點:介詞和介詞短語題型:選擇題...
  • 17925
25C時,0.1mol/L的3種溶液①鹽*②氨水③CH3COONa溶液。下列說法中,不正確的是(  )A.3種...
XX牌電熱壺型 號DSP﹣19B額定電壓220V額定功率880W頻 率50Hz熱水壺容量1.0L如表所示是某品...
低緯度是指(     ) A.0°~30°   B.23.5°~66.5°      C.30°~60    ...
ThesmogarrivedintheYangtzeRiverDeltaregiononNov.30,
  • ThesmogarrivedintheYangtzeRiverDeltaregiononNov.30,

  • 問題詳情:ThesmogarrivedintheYangtzeRiverDeltaregiononNov.30,_________theairquality   in12citiesoutof25wasratedasseverelypollutedbyDec≯1   A.where   B.when   C.which  D.what【回答】A知識點:定語從句題型:選擇題...
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