A:①
B:②
C:③
D:④
如图1,在等边△ABC中,点D是BC边的中点,点P为AB 边上的一个动点,设AP=x,PD=y,若y与x之间的函数关系的图象如图2所示,则等边△ABC的面积为( )
—Excuse me. Is the library open all day?
— . Only from 8 a.m. to 4 p.m.
当“嫦娥二号”发射时,太阳直射点( )