A:4+2 3
B:4+2 3 或2+ 433
C:2+2 3 或2+ 433
D:4+2 3 或2+ 233
抛物线y=1mx2的焦点坐标为( ) .
Most people are ____ that the 18th National Congress of the Communist Party of China is one of the most important meetings in history.