中国七大远程预警雷达

在矩形ABCD中,AB=20cm,BC=4cm,点P从A开始沿AB边以4cm的速度移动.点Q从C开始沿CD边以1cm的速度移动.如果点P和点Q分别从A和C出发,当P到达B时,两点都停止运动.设运动速度为S,t为何值时,四边形APQD为矩 Except that when I popped out they decided at the last minute that they really wanted a girl.decide 后面不是should do用动词原型吗 Why didn‘t you tell me?I ____ tell you .A ,do B,did C,am D,are Children should have free time[ ](relax)at school要写原因 Children should have free time __(relax) atChildren should have free time __(relax)at school.We will meet Mrs.wang if It __(not rain)tomorrow. （高中数学）已知数列{an}满足a1=3,an+1（n+1是脚标）=2an（只有n是脚标）+1,求数列的通项公式.我知道大概步骤,就是将式子化为an+1 +1=2(an+1).进而用累乘法求答案的.an +1 =2（an-1 +1）,an-1 +1=2（an-2 节选的这几段文字中,奥楚蔑洛夫对狗的态度有几次变化?原因分别是什么? 1、奥楚蔑洛夫在处理狗咬人事件上反复改判了几次?都是怎样判的?2、奥楚蔑洛夫不断变化的依据是什么?3第三题这个 3、奥楚蔑洛夫身上有没有始终不变的东西？我现在就要 5分钟之内给我 求一篇关于通讯报道的作文,要有关于同学的!600字,急. AD为△ABC的中线,∠ADB的平分线交AB与点E,ADC的平分线交AC与点F,ED=DN,求证 BE+CF>EF 一道初三的几何题.拜托了~我真的不会.谢谢 you___succeed if you keep up your good work Amust Bwill be sure to Cmust be able Dare sure to选哪一个,为什么? I'm sure I（）（）（）（） the exam.我确信我能通过这次考试.用be able to do sth仿写 捕蛇者说表达作者目的话原文中 Don't you let me go baby Don't you let me down you never say god l'm sure he will come____.He will win ____prize.A first,first B the first,the first C the first,first Tom ang his parents_________(arrive)in Beijing in three days,aren't they?are ariving为什么不能用are going to arrive?并说明in three days的用法及意义! Tom got up early to take the early bus转换Tom got up early( )( )( )take the 小学郑人买鞋的翻译 英语翻译全文翻译啊 用be aware of 造句.“他们没有意识到一件很重要的事情.”用到be aware of、They don't be ware of one important thing.还是 They aren't ware of one important thing.哪个是对的呢?请高手回答,不确定的朋友就免了. Be sure to write to us,()? a.will youBe sure to write to us,()? a.will you b.aren*t you c.can you d.mustn*t you 为什么选a? 用 be aware of 造句 人们的环保观念淡薄 teachers/be aware of /difficulties of 越简单越好. You are in a boat on a lake. You and your friend are going fishing.You fall into the lake,but you c Lucy 出生在哪里?她出生在巴黎.-____ ____Lucy _____?-She ___ ____ ___Paris. 你的笔友住在哪里?她住在巴黎.怎么翻译 她已被派往巴黎工作了 翻译 女人说这话代表了什么?Life is so short that you should not waste even one second on someone who does not appreciate and cherish you. what?can you tell me why? the sick的中文意思是什么? 有个英文歌中有句话,好像是the round,the round 重复了好久.是女生唱的,很有激情,请问是什么歌?我在很多地方都有听过,应该挺流行的.有次《舞动奇迹》也拿这首歌作为背景音乐.好像还有句话“