在标有指向标的地图上,指向标一般指向( )
A:正北
B:正东
C:正西
D:正南
证明:等腰三角形底边中点到两腰距离相等.(请画出图形并写出已知.求证及证明过程)
The winter holiday is coming. Do you know ________ during the holiday?