— Good luck______ you.
A:on
B:to
C:with
D:in
有下列四个命题,其中正确的有( )
①圆的对称轴是直径; ②经过三个点一定可以作圆;
③三角形的外心到三角形各顶点的距离都相等;④半径相等的两个半圆是等弧.
Stand up, Amy. How many birds?- Eight birds.