平均等待时间计算

平移、轴对称、旋转和位似有什么异同点 求托福,sat,GRE的词汇表,要可打印的! 平移 旋转 轴对称之间有什么区别和联系?区别是什么 联系是什么 不要说性质什么的.别跑题 急 对于考SAT的人来说,是新GRE红宝好还是老GRE红宝好? He walked into the roomand found a chair to set on.to set on 能否换成setting on?thinks a lot! 标志着中国的新民主主义革命取得完全胜利是什么 第一次世界大战的主要目的是什么? 氯化铜和碳酸钠到底能不能反应啊我是初中生,课本上的溶解表说碳酸铜不存在,可是参考书上却说你能, 碳酸钠 氯化铜 反应吗 CuCl2和Na2CO3会有反应吗?生成物是什麽?求化学方程式请加以语言解释~为何会这样（客观真理无从解释可免）~ she can't find his little son .she's---- a.worried b,worries c.worry d.worried about 旧民主主义革命和新民主主义革命的开始和结束标志,时间事件 the key to the door is missing这句话谁是主语,谁是定语.句子成分分析一下 I lose the key to the door.请问I lose the key to the door的中文是什么?还有I lose the key to the door与I lose the key of the door.它们有哪些不同?它们的意思相同么?key to the door是固定搭配么?它的中文是什么啊 与The key to the door.相关的短语? Rose is about her children.A.worry B.worried C.worries 什么叫旋转、平移、轴对称? 主要是电阻和电功的应用和公式（变形公式）化学上半学期的化学方程式和化学方程式的计算那块 初二和初三的物理哪些是难点? 高中选修3-1的物理题——重难点手册上的真空中有一直径为R的带电圆盘,圆心为O,圆盘外有A、B两点,其连线过圆心O点且与盘面垂直,若OA=AB=R,有一电荷在A点受带电圆盘的力为F,则它在B点时的受 初三 化学 物理 数学 重难点（四年制） the old man in blue coat ____.A.look worried B.looks worriedC.looked worries D.looks worrying the key to the door是否可以还原为the key which is to the door the old man looks 什么(worry)急 he looks very ( ) A,worry B,worries C,worried D,worrying 这四个选哪个,还有语法 The man looks o____sixth years old.应该是sixty.I'm so sorry! 人教版九年级英语单词 +课文听力下载mp3格式的能显示单词. 求人教新目标九年级英语单词课文听力MP3,音质好点的. From the __(happy) on his face ,we will knew that he failed the exam. I ----- from his face that he ----bad news.A.had seen,receivedB.would see,had receivedC.could see,receivedD.could see,had received You cantell from the < > on his face that he didn't do very well in the exam?A.communication B.appearanceC.feeling D.expression What is fairly clear, from the release of hydrogen and the fission products, is that all of these r请问如何翻译?What is fairly clear, from the release of hydrogen and the fission products, is that all of these reactors have probably had fuel ro