世界面积最小的大洲是： （ ） A、欧洲 B、南极洲 C、南美洲 D、大洋洲
下图为利用纯合高秆（D）抗病（E）小麦和纯合矮秆（d）染病（e）小麦快速培育纯合优良小麦品种矮秆抗病小麦（ddEE）的示意图，有关此图叙述不正确
(10·安徽D篇) My father was 44 and knew he wasn’t going to make it to 45. He wrote me a letter and hoped that something in it would help me for the rest of my life. Since the day I was
.It is said that the early European playing-cards ______for entertainment and education. A. were being designed B. have designed C. have been designed D. were designed
有一混合溶液,其中只含有Fe2+、Cl-、Br-、I-（忽略水的电离），其中Cl-、Br-、I-的个数比为2∶3∶4，向该溶液中通入氯气，使溶液中Cl-和Br-的个数比为3∶1
家谱是一种特殊的图书体裁，记录以血缘关系为主体的家族世系和家族重要人物事迹，是中国特有的文化遗产。这一体裁的出现与发展与下列哪一制度
．已知是方程x－ky=1的解，那么k=_______．
求证:经过平面外一点有且只有一个平面和已知平面平行 已知:∉α 求证:过点有且只有一个平面β∥α
