Most people have flown a kite or have seen one ride and dip(下降）in strong spring wind. Not so many people know that kites were first made in China thousands of years ago. The ancient Chinese were making and flying kites even before they were writing.

    A long time ago, the Chinese made kites to use in wars. They would fly these war kites in the dark. The kites were fixed(固定）so that they made strange sounds. Men at war would hear these sounds and run away. They thought those strange sounds were made by gods in the sky.

    The ancient Chinese also flew kites to bring good luck and to make their crops grow rich and tall. Sometimes they tied long strings(细绳）and hooks(钩) to their kites. Then they would fly the kites over water, letting the hooks hang down to catch fish.

    The Chinese use sticks(树枝), strings and paper for their kites. Some of these kites look like animals or trees. Others look like birds or houses.

小明学习生活用电常识后，在生活中更加注意观察家用电器．如图所示，他发现自己家洗衣机用的是三脚插头，标有“10A 250V”字样，其中的“10A”表示什么意思？仔细观察三只插脚，又有新的发现：标有“E”的脚比其它两脚稍长一些．他查看了其它三脚插头也同样如此，标“E”的脚稍长一些有什么好处？

设$a=\frac{4998}{4999}$，$b=\frac{6665}{6666}$，$c=\frac{9997}{9999}$，那么____  ＞____ ＞____ ．