①外植体消毒 ②制备MS培养基 ③接种 ④培养 ⑤栽培 ⑥移栽
A:①→②→③→④→⑤→⑥
B:②→①→③→④→⑤→⑥
C:②→①→③→④→⑥→⑤
D:①→②→③→④→⑥→⑤
椭圆x=3+3cosθy=-1+5sinθ(θ为参数)的两个焦点坐标是( )
____-(5.83+8.57)×2.4=36.84
--- ______, or we'll be late for the meeting.
--- It's only half past one by my watch. We have enough time left.