A:which; a
B:as; that
C:that; that
D:as; which
形近字单元词 。
幻____ 躁____ 侮____
幼____ 燥____ 悔____
过双曲线x2a2-y2b2=1(a>0,b>0)的右焦点F作圆x2+y2=a2的切线FM(切点为M),交y轴于点P.若M为线段FP的中点,则双曲线的离心率为( )