如图,DE是三角形ABC的边AB的垂直平分线,分别交AB、BC于D、E,AE平分∠BAC,若∠B=30度,则∠C=____ 度.
I'm ________ years old and it's my _______ birthday today.
下列现象中,能说明分子在不停息地做无规则运动的是( )