Besides calling 120, here is what you should do when no one is around to help.

If you get lost, you may stay where you can be seen clearly and try your best to have a rest. In a wide open area, make a colorful cross out of rocks to show where you stay.

When you choke at home, make a sudden hit against the back of the chair. If you can't breathe after six tries, call 120. Leave the telephone open until help arrives.

Use your hand or a scarf, or any dry cloth you can find, and push down on the wound until the blood stops running. Don't put the cloth around your leg tightly(过紧), or you may lose your foot.

When a fire breaks out, you must move close to the floor. Cover your mouth and nose with a wet towel, make you wet from head to foot if possible and find a safe place outside.

已知随机变量ξ服从正态分布N（0，σ²），若P（ξ＞2）=0.023，则P(-2≤ξ≤2)=（  ）

   Good morning! Now let me report the discussion work in our group. Wu Jun cleans up rooms  ____  weekends and Jia Mei likes cooking dinner with her mum. Wang Ping sometimes  ____ (wash) clothes for her family. As for me, I usually help my father water the flowers.
   In my opinion, it is necessary  ____  us students to do some housework by doing it, we can help our parents and understand them better. We’ll also learn to take care of  ____ . Besides, we can relax ourselves from hard work and develop our abilities.
That’s all. Thanks for  ____  ( listen)!