正方形ABCD的边长是2,E,F分别是AB和CD的中点,将正方形沿EF折成直二面角(如图所示).M为矩形AEFD内一点,如果∠MBE=∠MBC,MB和平面BCF所成角的正切值为,那么点M
分子中只含有x个碳碳双键的烯烃，其相对分子质量为M，Wg该烯烃与标准状态下体积为VL的氢气在一定条件下恰好完全反应，若以NA表示阿伏伽德罗常数的
Knowing how much her own children loved presents at Christmas, Ann Sutton always tried to seek help for one or two poor families．With a social worker mother, the Sutton children had inherited her co
_____ I shouted at the top of my voice _____ turn his head. A. Not until; did he B. Not until; he did C. Until; he did not D. Until; did he not
请看下面广告，然后做题 Happy Birthday To Wally Welcome to QuanJiao Zoo Our lovely and cute llama in our zoo, Wally will be 5 years old on November 14.Come and join us to ce
（2010·安徽野寨中学高三上第二次月考） 27. Those successful deaf dancers think that dancing is an activity __________ sight matters more than hearing. A. when
“凡士工商贾，皆赖食于农，以故农为天下之本务，而工贾皆其末也。”形成上述观念的根源（ ） A．重农抑商政策
以“忍不住______”为题写一篇作文。 要求：①在空格处填一个词或成语，把标题补充完整；②立意自定，文体自选；③字数不少于800字。
