如图,已知在△ABC中,AB=BC,∠B=120°,AB的垂直平分线交AC于点D。若AC=6cm,则AD=( )cm。
2
What are they doing? They ____________.
A.take photos
B.are taking photo
C.take a photo
D.are taking photos
目前常用的烧伤深度估计法是__________。