A:I1为零,I2为零
B:I1不为零,I2为零
C:I1为零,I2不为零
D:I1不为零,I2不为零
Our charity show for three hours this afternoon. We were tired but very happy.
如图,Rt△ABC的直角边BC在x轴正半轴上,斜边AC边上的中线BD反向延长线交y轴负半轴于E,反比例函数 y=kx(x>0)的图像经过点A,若S△BEC=10,则k等于____.