A:benefit; for the benefit of
B:benefit from; with the benefit of
C:receive goodness; in the benefit of
D:benefit from; for the benefit of
已知中心在原点的椭圆与双曲线有公共焦点,左、右焦点分别为F1、F2,且两条曲线在第一象限的交点为P,△PF1F2是以PF1为底边的等腰三角形,若PF1=10,椭圆与双曲线的离心率分别为e1,e2,则e1e2+1的取值范围是( )