菜豆种子萌发时,首先突破种皮的部位是( )
A:胚芽
B:胚轴
C:胚根
D:子叶
0.03×76.4=____
2.8×4.5=____
It's time ____ ____ ____ ____.
It's time ____ ____.
①____ ②____ ④____
⑤____ ⑦____ ⑧____
⑩____