al与cuso4反应现象

文章前面的话叫序,后面的话叫什么 两个全等的含30°两个全等的含30°的直角三角板叠放在一起,将△ABC绕直角顶点C逆时针旋转角α度(0<α＜90）至三角形A1B1C处,CB1交AB于D处.连接B1B要使三角形BB1D为等腰三角形则α应为多少,即叫b 3道数学3角函数题,一道30分,1、在平地上植树时,要求株距（相邻两树间的水平距离）为4米.如果在坡度为0.5：1的山坡上植树,也要求株距为4米,那么相邻两树间的坡面距离约为?2、如图,小明同 序言一般写什么,有什么作用 20°和-30°角,哪个大? 根据索引的顺序与表的物理序是否相同,可以把索引分为（）和非聚集索引 已知二次方程（ab-2b）x²+2（b-a）x+2a-ab=0有两个相等的实根,求1/a+1/b的值要过程 英语翻译已知检索式 ((ct or comput?(1w)tomography) and (solid(s)rocket?or propellant?) and (nondestruct?or ndt or nde or ndi )) /de,id,ti,ab,1990-2000 ,请写出它的含义. 已知二次方程(ab2b)x的平方+2(b-a)x+2a-ab=0有两个相等的实数根,则a分之2+b分之2= 向大家问几道数学题.（请用方程详细解答）1、商店运来两桶酒,大桶有酒120千克,小桶有酒90千克,两桶酒卖出同样多后,大桶剩下的酒刚好是小桶剩下的酒的4倍,两桶各剩下多少千克酒?各卖出 “科技信息检索与利用”的英文应该怎样翻译才地道? 主要的图书信息检索工具有哪些? Excel的升序和降序是什么意思 列出方程解决下列运用题 考勤系中升序降序是什么意思 [√6分之(√6-√12)x√3]+√6 初一计算题提高准确率我准确率有些低 she has already bought the book(改为否定句） she ____ bought the book_____.I have always wanted to _stay with my parents_ in Beijing(对划线部分提问）what have you always wanted _____ _______in Beijing.Kate moved to Beijing two years ago 最好是方程计算：10111213141516171819×99989796959493929190-10111213141516171818×999897969594939291 Where is the beautiful picture?You bought it last week.连成一句话 Where is the beautiful picture?You bought it last week.（合成一句） 函数y=f(x)当x属于【a,b】时值域为【ka,kb】（k》0）则称y=f(X)为k倍值函数.若f(X)=lnx+x是k倍值函数求实数k的取值范围 1.某项工作,甲独做4天完成,乙独做8天完成,现在甲先做一天,然后和乙共同完成余下的工作,问完成这项工作共需要几天?2.已知兄弟三个岁数的和是30,如果大哥的岁数减2,二哥的岁数加2,弟弟的岁 She went to Bristol yesterday（用where针对Bristol提问） where did she went yesterday? She went to the countryside( ).A.in the morning at nine on June first,1968 B.on June first,1968 in the morning at nine C.at nine in the morning on June first,1968 D.on June first,1968 at nine in the morning could you please ________ the picture on the wall?a pick up b look up c get uo d put up 如果(cosα)^2-(cosβ)^2=a,则sin(α+β)sin(α-β)=?我的步骤是：(cosα)^2-(cosβ)^2=a（cosα-cosβ）（cosα+cosβ）=a【因式分解了】（2· cosα+β/2 · cosα-β/2）（-2· sinα+β/2 ·sin α-β/2）=a【和差化积】然后后面 如果sin（π/2+α）=cosα,sin （π/2－α）=cosα,那么sin(π/2+α)=sin(π/2-α)对吗? sin(2π-a)cos(π/2-a)/cos(π-a)sin(π/2+a)化简…再求值（要有大概过程） The l___of the songs are very beautiful and sound like a poemPlaying is an art that is played by pulling piying By s ___His grandpa died of h_______disease last year Do you like Cai Yilin's songs?Yes ,they_____really beautiful .A look B listen Csound为什么不是listen? do you like Jay Chou's songs?Yes,they()raelly beautiful.A.lookB.listenC.soundD.see