scp343

有A B C三种零件,分别为a个,300个,200个,现采用分层抽样法抽取一个容量为45的样本,A种零件被抽取20个,C种零件被抽取10个,则此三种零件共有多少个? 一道高三文科数学题###函数y=f(x)在区间(0,正无穷)内可导,导函数f'(x)是减函数,且f'(x)>0.设x0属于（0,正无穷）,y=kx+m是曲线y=f(x)在点(x0,f(x0))处的切线方程,并设函数g(x)=kx+m（1）用x0,f(x0),f'(x0)表示m 求一段关于女孩可爱的描写.词语,语句都可.求一段关于女孩可爱的描写.词语,语句均可. 描写可爱的小孩子说话时的词语 should 后面必须加动词原形吗, should 后面是加动词原形还是ing形式 what引导的主语从句谓语动词单复数?例：what they need is/are two books.不要从网上找 我查过了说什么的都有 should后面要不要加动词原形如题 What只能在主语从句里做主语?专业点、我是分不清宾语/主语从句 和定语从句、 should 后面是不是必须跟动词原形?比如:we should first read the real estate ads in the newspater.还有这句话是否可以改成:Firstly,we should read the real estate ads in the newspater.如果可以,第一句话里的first 是什么 what引导主语从句和which引导的主语从句有什么区别 主语从句问题,连接代词what引导的主语从句,what充当什么成分.what you told me just now was really a surprise比如这个句子,what充当什么,如果是充当主语,you就是主语啊,更不可能是宾语或表语.那是否可以 有没有描写儿童的古诗 that可以在宾语从句中作从句的主语或宾语吗?what可以在定语从句中作从句的主语吗?如果可以,请各自举一例,谢谢 that作引导主语从句时,可不可以引导what.that what happened to her surprised me.这句话是不是正确的?句中that和what好像都是名词性引导词,搭配起来感觉很怪.“发生在她身上的事使我惊讶”这句话应该 非谓语动词的用法和主语从句以WHAT和THAT的区别 在主语从句中that和what有什么不同 怎样判断判断主语从句和强调句.都是it is...that... 是不是所有的主语从句都可以改成It is...that例如：Whether we will go for an outing tomrrow remains unknow.Who will be our monitor has't been decided yet.Whom we must study for is a question of great importance.What caused the accident 英文文章改错这是我写的一篇英文影评,楚门的世界At the begining of the movie,Truman's life was peaceful and warn.He had his wife,his job and his own life.But at last he found that all the things in his life were not real.He was jus 英文作文改错,Why I choose to read postgraduate?At present,more and more college students choose to read postgraduate.No doubt their reasons for doing that are different.Perhaps,some students think that postgraduates can pave the way for good jo 英文作文改错希望把这几段改对了,或者写的更合适 In the life there are many people doing different job. Every job is important in the life, someone will change their career, what do you think the reasons might be for that? I guess 帮助英文文章改错英语牛人帮忙,虽然本人是英语牛人团团员,但这份题目非常重要,因此想做到100％,而且,这是新加坡中学题目,估计至少相当于四级,请诸位帮帮小弟.这是一篇采访稿,内有20个 英语改错…和作文… "售后采购”英语翻译, It’s+形容词+that+从句.用句型造句子谢谢了! 1.it is 形容词 that从句 同样是做主语这个that从句能改成what名词从句吗?2 动词+it+宾补+后置定语 ①后置定语为to do 或是that从句（除定语从句,同位语外）要保留形式宾语it.②后置定语为what从句 It+be+形容词或过去分词+主语从句 当形容词为important时,要用虚拟语气.It is important that the committee be informed about the project at once.我不是很懂虚拟语气. it's+形容词/(v+ed)+that属于什么从句例：It's said that dogs are color blind.It's certain that you should leave.这两种属于什么类型的从句? 动词如何变动名词 主语 be+so+adj+that从句 求~~ 用英语怎么说Sally是一个女孩