题干
4. It is _________ that you haven’t got the right answer. You have m
isunderstood our real intention.
A：sure
B：obviou
C：possible
D：Likely
答案(点此获取答案解析）
B
、
在
轴上,A为双曲线上一点, 
轴, 
,则双曲线的离心率为（ ）