-- Could you turn down your radio, please? It's noisy.
-- .
-- I ask you to turn down your radio a little.
A:I beg your pardon
B:I'm sorry
C:Do you want to go
D:Yes, of course
如图所示,⊙D 的半径为3,A是圆D外一点且AD=5,AB,AC分别与⊙D相切于点B,C.G是劣弧BC上任意一点,过G作⊙D的切线,交AB于点E,交AC于点F.
下面细胞器中,参与有机物合成作用的是①核糖体 ②线粒体 ③内质网 ④高尔基体 ⑤叶绿体