阅读下面短文，从方框中选出适当的词，并用其正确的形式填空，使短文意思完整。每词限用一次。

   It’s very important for everyone to protect the environment. As a student, I always try my ____  to save energy at home. I turn off ____  when I don’t need them. And I try to save water when I wash the dishes. I don’t ____  bottles or newspaper away because it’s better to recycle them.
   I think everyday activities at home can make a difference to the environment. I feel proud of ____, and I will not only keep saving energy but also advise others to do the same things as me. If everyone cares about ____  the environment, I’m sure we’ll have a better life.

一个人骑车以6米/秒的速度匀速追赶停在交通信号灯前的汽车，当他离汽车25米时，交通信号灯由红变绿，汽车开始做变速直线行驶（汽车与人的前进方向相同），若汽车在时刻t的速度v（t）=t米/秒，那么此人（　　）

如图，点C、D在线段AB上，△PCD是等边三角形，且△ACP∽△PDB，求∠APB的度数．