已知随机变量（X,Y）的概率分布为则cov（X,Y）

deal的用法和现在进行时是什么 Did they take a train to Hangzhou last Friday?改同意句Did they take a train to Hangzhou last Friday?Did they ____ ____ Hangzhou ____ ____ last Friday? 大学四六级英语成绩单什么时候下发 反犬旁+蜀是什么字 四六级成绩什么时候能查啊 中央人民广播电台经济之声英语之夜在长沙的调频是多少? mike is a ambulance man.哪个错了? 原来中央人民广播电台经济之声的英语之夜栏目现在还有么?有的话什么时候播啊? 中央人民广播电台经济之声英语之夜里英语学堂的杂志是哪一本? he is running 填什么 he is running while she is swimming这句我怎么总感觉怪怪的 可是我读起来总是觉得怪怪的总感觉 错了 He is s____about running?怎样翻译整个句子？ 关于经济之声“英语之夜”!最近中央人民广播电台经济之声的“英语之夜”节目没了,不知道是节目取消了还是改时间了,有知道的请在这做个回答, 中国广播网中的英语之夜停播了,我想问问还有哪些英语节目可以收听 . 英语翻译The company that supplied wine to us last,has had to purchase wine at $1.50p/L for low quality stock to blend with their bulk range and up to $6.00p/L for premium,which is what you are looking for.Farmers are paying $1000.per megalitre of 英语翻译英文文献里的,审计学,统计模型,关键是 the variable of interest 要怎么翻译和理解? 原来中央人民广播电台经济之声的英语之夜栏目现在还有么?什么时候播啊? 在武汉,中央人民广播电台经济之声的频率是多少?是不是每个地方都不一样啊?晚上有一档英语节目是几点开始的? The support___(most) comes from the local people and businesses.用单词的适当形式填空 I want to find a pen pal from the US or the UK or the people who come from the English country.like the title,I really want to find a pen pal to improve my English skills.Please send a e-mail to hudaviddent@aim.com.或者给我推荐一个交友网 We'll go out for a walk with you做同义句 用括号内所给单词的适当形式填空.亲,1.I want ___（work) in a post office2.Today is his ____(twenty) birthday .3.____(be) there any pictures on the wall.4.Let's go to see the pandas___( one ).5.the star loves playing ___(sport ).6.Mr.Gr It took him four years to stage this elaborate jobke simply to prove that critics do not always know what they ate talking about.这句话里面为什么要把about放在句末呢?倒装句么? 英语翻译不好意思，上面打错了。哪句话应该是I have got a useful contact in there。还有，I'd rather you would happen anything about it right now。这句话怎么理解？ I WILL COME ON,CHANGE THE IMPOSSIBLE INTO THE POSSIBLE是什么意思? 怎样学英语进步快? 怎样学英语还能进步快些?需要买什么辅导书和某些工具书吗? 怎样学英语、才会进步得更快!多说、多看、多记 什么血统鸽子最好 Love doesn't rush as the whole 和as a whole的区别 英语翻译2.How do people live in places far away?3.What's life in the deepest part of the sea?4.It was Waldi,a colourful dog.in the past 28 Olympic Games,some hosting countries had as many as three Olympic mascots.5.No one can say No to a kid's sm