[单选题]设A,B,C,D是空间不共面的四点,且满足,则△BCD是A.钝角三角形 B.锐角三角形 C.直角三角形 D.不确定
[单选题]To understand the grammar of the sentence, you must break it ________ into parts.[ ]A. downB. upC. offD. out
[单选题]记实数x1:x2…中的最大数为n ak{x1:x2…},最小数为min{x1:x2…}.已知△ABC的三边边长为、、(a≤b<c),定义它的倾斜度为a bt=m axbb-c●m1nbc a则“t=1”是“△ABC为等边三角形”的( )A.充分布不必要的条件B.必要而不充分的条件C.充要条件D.既不充分也不必要的条件
[单选题]They argued _____ the matter the whole afternoon, and at last agreed____ the date for the next meeting.[ ]A. with; on B. on; over C. about ; on D. over; over
[单选题]— The weather is too cold ____ March this year.— It was still ____ when I came here years ago.A. for; colder B. in; cold C. in; hot D. for; hotter
[单选题]Success in life doesn’t happen_____. It’s the result of devoting yourself to what you’ve set out to do. A.by designB.by natureC.by chanceD.on purpose
[单选题]下列命题中,正确的命题有( )(1)用相关指数y来刻画回归效果,y越接近0,说明模型的拟合效果越好;(2)将一组数据中的每个数据都加上或减去同一个常数后,方差恒不变;(3)设随机变量服从正态分布N(0,1),若P2>1)=p,则P(-1<2<0);(4)回归直线一定过样本中心点A.1个B.2个C.3个D.4个
[单选题]已知点O,N,P在△ABC所在的平面内,且,,,则点O,N,P依次是△ABC的A、重心、外心、垂心 B、重心、外心、内心 C、外心、重心、垂心D、外心、重心、内心
[单选题]AB?+AC-BC等于( )A.2ABB.3ABC.BAD.CA
[单选题]Eggs are________ size. Which is wrong[ ]A. classified according to B. sorted according to C. classified by D. classified as
[单选题]When questioned, he was too shocked to give a(n)?of what had happened when the attack took place.A.assessment B.account C.survey D.summary
[单选题]While I was making the model plane,my little nephew kept asking me questions with great ______ .A.wonderB.patienceC.doubt D.curiosity
[单选题]在△A.C中,D是BC边上一点,则等于( )A.B.C.D.
[单选题]给定空间中的直线l及平面α,条件“直线l与平面α内两条相交直线都垂直”是“直线l与平面α垂直”的 [ ]A.充分不必要条件B.必要不充分条件C.充要条件D.既非充分也非必要条件
[单选题]We must read not only between the lines, but sometimes ________ the lines so that we can fully understand the writer.[ ]A. withinB. among C. besides D. beyond
[单选题]Before you leave Beijing for New York, you should be familiar __________ English.? [ ]A. with B. toC. onD. about.
[单选题]The old man put on his glassessee better. [ ] A. on purpose B. in order thatC. so asD. in order to
[单选题]“x<﹣1”是“x2﹣1>0”的[ ]A.充分而不必要条件B.必要而不充分条件C.充要条件D.既不充分也不必要条件
[单选题]With several rounds of talks, the union leaders successfully ?an agreement for a shorter working week.A.deservedB.negotiatedC.persuadedD.demanded
[单选题]Im sorry its ?my power to make a final decision on the project.A.overB.aboveC.offD.beyond
[单选题]What’s your attitude ______ going abroad?.A.in B.of C.over D.to