对于任何实数，我们规定符号$\left|\begin{array}{cc}a& b\\ c& d\end{array}\right|$的意义是：$\left|\begin{array}{cc}a& b\\ c& d\end{array}\right|$=ad﹣bc．

（1）按照这个规定请你计算：$\left|\begin{array}{cc}5& 6\\ 7& 8\end{array}\right|$的值．

（2）按照这个规定请你计算：当x²﹣3x+1=0时，$\left|\begin{array}{cc}x+1& 3x\\ x-2& \mathrm{}x-1\end{array}\right|$的值．

    Here are some tips about how to keep healthy.

1) Healthy food is important. If you want to keep healthy, eat lots of fruit and vegetables. Don't eat much meat.

2) Water is important. Drink water every day. Milk is good for you, too. Don't drink sweet drinks.

3) Exercise is important. You can ride your bike or play soccer. Going swimming is a good idea.

4) Clean air is important. If you are free, you can go to the park and enjoy clean air.

5) Your teeth are important. You should brush your teeth twice a day.

6) Sleep is important, too. Go to bed early. Don't stay up late, or you will feel sleepy.

兔妈妈拔了65根胡萝，平均分给13只小兔，每只小兔可以分得____根胡萝卜?