Can these children look after ____ when their parents are not at home. (them)
已知:如图,AB是⊙O的直径,CD是⊙O的弦,AB,CD的延长线交于E,若AB=2DE,∠C=40°,求∠E及∠AOC的度数.
以下对核外电子运动状况的描述正确的是( )