请认真阅读下面短文，并根据短文内容回答问题。
Dear Helen,
      Thanks for your last letter. Yes, I'm enjoying myself on my exchange program in France. It's even better than I thought it would be. I was a bit nervous before I arrived here, but there was no reason to be. My host family are really nice. They go out of their way to make me feel at home. And you wouldn't believe how quickly my French has improved! I'm very comfortable speaking French now. Although I still make lots of mistakes, it doesn't make me worried as it used to. My biggest challenge (挑战) is learning how to behave (表现) at the dinner table. As you can imagine, things are really not the same as the way they are at home. For example, you shouldn't put your bread on your plate. You should put it on the table! I thought that was very strange at first, but now I'm used to it. You shouldn't eat anything with your hands except bread, not even fruit! (You have to cut it up and eat it with a fork.) Another thing is that it is very rude to say you're full. If you don't want any more food, you should just say, “It was delicious.” Also, it's rude to put your hands in your lap. You should always keep your hands, but not your elbows (肘部), on the table. I have to say, I find it difficult to remember everything, but I'm gradually getting used to things and don't find them so strange any more.
      I'll write soon and tell you more about life in France. Hope you're having a good school year.
Yours,
Li Ying

2012年3月5日，备受世界瞩目的普京，再次当选俄罗斯总统．被称为世界舞蹈奇葩的是俄罗斯的（　　）

已知从这30名青少年中随机抽取1名，抽到肥胖青少年的概率为 $\frac{4}{15}$ ．