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图中,EB为半圆O的直径,点A在EB的延长线上,AD切半圆O于点D,BC⊥AD于...
图中,EB为半圆O的直径,点A在EB的延长线上,AD切半圆O于点D,BC⊥AD于点C,AB=2,半圆O的半径为2,则BC的长为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103102347004639337/SYS201311031023470046393013_ST/images0.png)
A.2
B.1
C.1.5
D.0.5
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