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已知:如图,⊙O是△ABC的外接圆,D为CB延长线上一点,∠AOC=130°,则...
已知:如图,⊙O是△ABC的外接圆,D为CB延长线上一点,∠AOC=130°,则∠ABD的度数为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101707494455045/SYS201311031017074944550023_ST/images0.png)
A.40°
B.50°
C.65°
D.100°
考点分析:
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