答:至少再经过40分钟后又同时发车.
- Who gets up ______ in your family?
- My mother. She has to cook breakfast for my father and me.
食用新鲜的蔬菜和水果能预防坏血病,是因为蔬菜和水果中含有大量的( )
如图甲所示,在直角梯形ABCD中,AB∥DC,∠B=90°.动点P从点B出发,沿梯形的边由B→C→D→A运动.设点P运动的路程为x,△ABP的面积为y.把y看作x的函数,函数的图像如图乙所示,则△ABC的面积为( )