有一瓶Na2SO3溶液，由于它可能部分被氧化，某同学进行如下实验：取少量溶液，滴入Ba(NO3)2溶液，产生白色沉淀，再加入足量稀硝酸，充分振荡后，仍有
在2A＋B 3C＋4D反应中，表示该反应速率最快的是 A．υ（A）＝ 0.5 mol/（L·ｓ） B．υ（B）＝ 0.3 mol/（L·ｓ） C．υ（C）＝ 0.8 mol/（L·
It was Tom who started the song, and everyone ____. A. divided up B. put it up C. took it up D. held it up
如图1-1-11,梯形ABCD中,AD∥BC,对角线AC、BD分别交中位线于H、G,且EG∶GH∶HF=1∶2∶1,那么AD∶BC等于____________.图1-1-11
(2010·河北省，一，5分)阅读下面这首唐诗，回答问题。(5 分) 酬乐天扬州初逢席上见赠 巴山楚水凄凉地，二十三年弃置身。 怀旧空吟闻笛赋，到乡翻
如图，ABCD-A1B1C1D1为正方体，则以下结论： ①BD∥平面CB1D1； ②AC1⊥BD； ③AC1⊥平面CB1D1 其中正确结论的个数是 （ ） A
-Many beautiful flowers ________ around our school every year. - Yes, _______ beautiful our school looks! A. are planted; what B. are planted; ho
Although many Chinese students say that their knowledge of English grammar is good, most would admit that their spoken English is poor. Whenever I speak to a Chinese student, they always say,“My spo
，函数
的图像可能是 （ ）
