Emma goes to school at 7: 30 and she is late for it.
A:never; always
B:always; often
C:always; never
D:often; always
Are____going to visit Beijing?
如图,一次函数y=﹣x+2的图象与两坐标轴分别交于A、B两点,点C是线段AB上一动点,过点C分别作CD、CE垂直于x轴、y轴于点D、E,当点C从点A出发向点B运动时(不与点B重合),矩形CDOE的周长( )