Boys and girls,

Attention, please! Do you know 1to keep safe in our daily（日常的）life? Today I’d like2 you some ways to keep safe.

1  Always play in a 3 place. A park is a safe place4 there are no cars or buses in it.

2  5 the traffic rules, please! Before crossing a road,6 and look both ways ——look left, look right and look left 7.

3  Never put your head or hands 8 a car, a bus or a train. Many people get 9 or lose their lives by doing so.

4  Don’t 10 a stranger（陌生人）or go with him/her.

That’s all. All the students should obey the rules anytime(任何时候).

设点P是双曲线$\frac{x^2}{a^2}-\frac{y^2}{b^2}=1\left(a>0,b>0\right)$与圆x²＋y²＝a²＋b²的一个交点，F₁, F₂分别是双曲线的左、右焦点，且|$\overrightarrow{P{F}_1}$|＝$\sqrt{3}$|$\overrightarrow{P{F}_2}$|，则双曲线的离心率为（   ）

已知该商品的进价为每件30元，设销售该商品的每天利润为y元．