“盘旋在崇山峻岭之上/绵延峭拔的八达岭啊/舞起矫健的巨龙/短兵相接的年月/你是抵御外敌入侵的壁垒/和平建设的年代/你是显示民族气魄的支柱……”诗中赞美的我国古代的伟大工程是( )
A:都江堰
B:长城
C:赵州桥
D:大运河
青霉素是著名的抗生素药物.下列微生物可以提取青霉素的是( )
请从右栏中为左栏的图片选择相应的文字描述
Picture
Description(描述)
① ____
A. Aren't they lovely? They walk on the ice and snow. They can also swim. Do you want to know more about them?
② ____
B. Do you often watch him play basketball? If you do so, what do you think of him? Good or awesome(令人敬畏的)?
③ ____
C. — I can't find my keys.
— Let me help you.
④ ____
D. — Where's your pen friend from?
— Sydney. Oh, it's in Australia.
⑤ ____
E. Do you enjoy playing soccer? Look! They often play after school. How excited they are!
设集合A={x||x﹣a|<2},B={x|2x-1x+2<1,若A⊆B.求实数a的取值范围.