通过以下反应均可获取H₂．下列有关说法正确的是（  ）

①太阳光催化分解水制氢：2H₂O（l）═2H₂（g）+O₂（g）△H₁=571.6kJ•mol^﹣1

②焦炭与水反应制氢：C（s）+H₂O（g）═CO（g）+H₂（g）△H₂=131.3kJ•mol^﹣1

③甲烷与水反应制氢：CH₄（g）+H₂O（g）═CO（g）+3H₂（g）△H₃=206.1kJ•mol^﹣1．

已知向量$\overrightarrow{a}$=（x²﹣3，1），$\overrightarrow{b}$=（x，﹣y）（其中实数x和y不同时为零），当|x|＜2时，有$\overrightarrow{a}$⊥$\overrightarrow{b}$，当|x|≥2时，$\overrightarrow{a}$∥$\overrightarrow{b}$．

（I）求函数式y=f（x）；

（II）若对∀x∈（﹣∞，﹣2}∪2，+∞），都有mx²+x﹣3m≥0，求实数m的取值范围．

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有一项为多余选项。                                                            

     Why do we play sports? You might say “to get exercise” and you'd be right. To have fun? That's true, too. But there's more. ____ According to a study, girls who play sports get a lot more than just fit.

　　Girls who play sports do better in school. You might think that playing sports will take up all your study time. ____  Exercise improves learning, and memory, which can give active girls an advantage in the classroom.

Girls who play sports learn teamwork and goal-setting skills. ____ When you work with coaches, trainers, and teammates to win games and achieve goals, you're learning how to be successful. Those skills will serve you well at work and in family life.

　　Playing sports improves self-confidence.  ____ Why? It builds confidence when you know you can practice, improve, and achieve your goals. Sports are also a feel-good activity because they help girls get in shape, keep a healthy weight, and make new friends.

  ____ Playing sports can reduce stress and help you feel a little happier. How? The brain chemicals released during exercise improve a person's mood. Friends are another mood-lifter．And being on a team creates tight bonds between friends. It's good to know your teammates will support you－both on and off the field!