—How long have you __________ here?

—For two days. I __________ here the day before yesterday.

① $AB$ 与 $DE$ 所成角的正切值是 $\sqrt{2}$ ；

② $AB$ ∥ $CE$ ；

③ $V_{B-ACE}$ 的体积是 $\frac{1}{6}{a}^2$ ；

④平面 $ABC$ ⊥平面 $ADC$ ；

⑤直线 $EA$ 与平面 $ADB$ 所成角为 ${30}^{\circ }$ ．

其中正确的有____．（填写你认为正确的序号）

古时有“守株待兔”的寓言．假设兔子质量约为1kg，以10m/s的速度大小奔跑，撞树后反弹的速度为1m/s，则兔子受到撞击力的冲量大小为 （   ）

    I will have a holiday next week and I can't decide what to do. I have a lot of work to do 1 and this would be a good chance 2. But I don't like 3 the holiday in such a way.I can work at home all the rest of the year.

    Last year I went 4 to the mountains. 5 there was beautiful， but it is too cold this time of a year. And it's really6 far to go for a short holiday. I decide 7 this isn't a good time to8the mountains.But I9to go somewhere else.Perhaps this would be a good chance to go to the beach（海滨）.I like to go for walks10the seashore 11the warm sunshine and watch the water. It's only eight miles away and I could get there 12about two hours. After thinking it13，I am sure that this is a 14time for the seashore than15.

    Oh， here is a 16from Jim. He 17 he is going to his house in the mountains for the18，and he19me to go with him.20 giving it some more thought， I wrote back to Jim and thanked him for that.