对于气体压强的产生，下列说法正确的是（  ）

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　       1   you can't eat up your whole lunch, do you throw it away?  Most kids do. But Mr. Zhang won't let you! Mr. Zhang is a teacher at a senior middle school. The 60-year-old man saw a student    2    a half piece of cake into the trash can. He was   3   angry that he   4    and ate it.

        “I just didn't want    5    food, ” he said. “I had little to eat when I was young. ”

If you have   6    been hungry, you can never understand how precious（宝贵的） food is. You might have enough food    7  . But many people didn’t. Do you know that there are about 300 million hungry kids in the world?  Every five seconds, a child dies    8    hunger somewhere in the world.

         What can you do? The first step is changing your attitude. Respect all the work what goes into making food. Farmers work hard to plant crops. Your parents spend a lot of money    9  food for your family. When you throw away your lunch, you are throwing away their hard work.

         So, if you can't finish    10    a big piece of cake, wrap it up and take it home. Or remember to buy a small one next time.

【自然灾害与防治】

2014年12月至2015年2月，莫桑比克北部和中部地区出现了严重的洪涝灾害，已造成至少158人死亡，约20万人受到影响，其中赞比西亚省受灾情况最严重。

分析赞比西亚省洪涝灾害严重的原因，指出莫桑比克应对洪涝灾害应采取的措施。