A:③④⑤⑧
B:④⑤⑦⑧
C:④⑤⑧
D:③④
如图,AB是⊙O的弦,∠AOB=120°,AB=a,则OA=____ .
--- Thank you for helping me with my physics. --- ______. I hope you can do better in it.
zàn____
yì____
dǎo____
hùn____
yáo____
hūn____
zhēn____
混
捣
暂
谊
侦
谣
昏