决定牙齿形状的是()
A.成釉器
B.牙 * *
C.牙囊
D.成釉细胞
E.星网状层细胞
参考答案:B
___ from space, the earth with water ___70% of its surface looks like a "blue blanket".
A.Seen ;covered
B.Being seen; covers
C.Seeing; covering
D.Seen; covering
配置E1业务,E1业务默认配置的发送时钟是()时钟。