在下列各数：3.1415926、$\sqrt{\frac{49}{100}}$、0.2、$\frac{1}{\pi }$、$\sqrt{7}$、$\frac{131}{11}$、$\sqrt[3]{27}$中无理数的个数是（　　）

完形填空

    I like English very much. I think English is very important and 1. Here are my opinions of 2English well.

    I think there are many ways 3learn English. For example, asking the teacher 4 help is very helpful. One of my good 5said he had trouble 6English. His 7 English is very poor. So he reads aloud every morning. Now he can speak English very well. Watching English shows on TV can also be helpful. You can learn many words 8them. Remember "Where there is a 9, there is a way." Believe you can do it 10 .

8500里有____个100。

日常生活中常见到下列现象，其中属于化学变化的是（    ）