A:C3H3
B:C4H4
C:C5H5
D:C6H6
—Can you guess _______ the new T-shirt last week?
—Sorry, I don't know.
把少量下列物质分别加入水中,充分搅拌后,不能形成溶液的是( )
方程x= 4−3x 的根是____.