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EF是平行四边形ABCD的对角线在AC上的两点,且AE=CF,求证:DF平行BF Could you help me carry this heavy box,please?A．I don't mind B.It doesn't matterC.With pleasure D.It was a pleasure请问选哪个?请一一分析．谢谢... would you please help me___the heavy box?A carry B carrying C carried D to carrying 设A是三阶矩阵,a1,a2,a3是列向量,且线性无关,Aa1=a1-a2+2a3,Aa2=a1+a2+3a3,Aa3=-a1+a2-3a3,求A的行列式 A为3阶矩阵,a1,a2,a3为3维列向量组,（Aa1,Aa2,Aa3）为什么根据分块矩阵乘法可分为A（a1,a2,a3）? 初三化学第13题,快来啊啊啊啊啊啊啊啊啊 把少量物质分别加入到另一物质中,充分搅拌,可以得到溶液的是?A碘加入汽油中D高锰酸钾加入汽油中BC两个选项肯定错的,我就不打上来了,我就是在AD这里纠结啊.我有看到碘和高锰酸钾都可以 已知四边形abcd是等腰梯形 cd平行ba 将三角形abd沿ab对折得到△abe 四边形aebc是 1、从海水中提取食盐,是用__结晶的方法,此方法一般适用于固体溶解度受___的固体物质,从KNO3饱和溶液中得到KNO3晶体,是用___结晶法,此方法适用于固体溶解度受___的固体物质 can i help you yes ,can you tell me ______A.where is the washing roomB.which is the most popular book选哪个,为什么 如果一个水平放置的图形的斜二测直观图是一个底角为45度,腰和上底均为1的等腰梯形,那么原图形的的面积是 下底怎么求 根据对话内容,选择恰当的句子补全对话 A:Good morning .Can I help you B:Yes ,please（A）根据对话内容,选择恰当的句子补全对话A:Good morning .Can I help you B:Yes ,please ( )A:We have many different kinds of jeans here . could you tell me how to remember new words qucikly yes ,i think a __ tree can help you a lot.A.grammar B.equation C.vocabulary D.punctuation 设三维列向量a1,a2,a3线性无关,A是三阶矩阵,且有Aa1=a1+2a2+3a3,Aa2=2a2+3a3,Aa3=3a2-4a3,试求A的行列式 初三化学选择快来啊啊啊啊啊 Would you please help me with my homework是什么意思 help me with 近义词would you please help me with my homework?A give me help in B give me a big hand答案是a,b为什么不行,还有 give me help in 是固定搭配吗? 我从来没见过,只见过help sb (to)do 和help sb with sth.谢谢 Would you please help me with my English after the homework ____(do).这儿的after是什么词性啊？ 1.Would you please help me with my English after the homework ___________(do) 2.I’m afraid the trousers of your size __________________(sell) out 如图,将图一所示的正六边形进行分割得到图二,再将图二中最小的某一个正六边形按同样的方式进行分割得到图三,再将图三中最小的某一个正六边形按同样的方式进行分割……,则第n个图形 将图11-11①所示的正六边形进行分割得到图11-11②,再将11-11②中最小的某一个正六边形按同样的方式进行分得到图11-11③,再将11-11③中最小的某一个正六边形按同样的方式进行分割······则 下图是用火柴棒摆成的由若干个正六边形组成的一个图形,从中心仅有一个正六边形算起,图6有3层．如果再摆2层,那么一共需要（　）根火柴棒． Could you help me carry the heavy cardboard box?Yes,I—— A can B could C will D might Can i help you with the heavy box?a. That's very nice of you .b. You can, pleasec. Thank you for your helpd. With pleasure __-Excuse me ,could you help me carry the heavy box __( )__( ) A.Yse,I could B.It doesn't matterC.With pleasure D.Don't mention it Excuse me,S_____.Could you help me carry the heavy box? Excuse me,could you help me carry the heavy box?with （p ) 在括号中用所给单词适当形式填空L'm glad you can come to my birtday party.Please help (y ) to the cakes.3 The doctor will bo (f ) in haif an hour.Can you wait that long? 若基因中脱氧核苷酸的排列顺序发生变化,那一定会导致A.遗传性状的改变B.遗传密码的改变C.氨基酸结构的改变D.DNA的结构发生改变为什么 一列火车从威海开往济南,已经行了全程的2/5,行了240千米.威海距离济南多少千米?算式 一列火车从威海开往济南,已经行啦全程的5分之2,还剩96千米,威海距济南多少千米给赏金的 为什么葡萄糖由血浆进入红细胞的运输方式是协助扩散? 已知,如图,DA⊥AB,DE平分∠ADC ,CE平分∠BCD,且∠1+∠2=90°