地球每天自转1圈,24小时自转360°,那么本堂地理考试从考试开始到考试结束,地球要向东转过( )
A:30°
B:45°
C:15°
D:60°
如图,△ABC内接于⊙O,D为线段AB的中点,延长OD交⊙O于点E,连接AE,BE,则下列五个结论①AB⊥DE,②AE=BE,③OD=DE,④∠AEO=∠C,⑤弧AE=12弧AEB,正确结论的个数是( )
—How about joining us in the summer camp?—I wish I could, ___________ I have to practice for the piano test.