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如图,A、B、C是⊙O上的三点,已知∠O=60°,则∠C=( ) A.20° B...
如图,A、B、C是⊙O上的三点,已知∠O=60°,则∠C=( )
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A.20°
B.25°
C.30°
D.45°
考点分析:
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