选出相对应的答语。
①Do you like summer? ____ A. They're kites.
②Can you play in the park in spring?____ B. I like rabbits.
③Would you like an ice cream?____ C. Yes, we can.
④What do you like?____ D. We can eat fruit.
⑤What can we do in autumn?____ E. Yes. I like summer.
⑥What are they?____ F. Yes, please.
，虚轴的一个端点为
,如果直线
与该双曲线的一条渐近线垂直，那么此双曲线的离心率为