孤立波
参考答案：
孤立波的波长波周期都趋于无这穷大，波面全部在静水面以上。孤立波是一种推移波，水质点只朝波浪传播方向运动而不向后运动。
In the following essay, each blank has four choices. Choose the best answer and write down on the answer sheet.
To a router, a flow is a (71) of packets that share the same characterstics, such as traveling the same (72) , using the same (73) , having the same kind of security, and so on. A router that supports the handling of flow labels has a (74) table. The table has an entry for each Active flow label; each entry defines the (75) required by the corresponding flow label.
（74）是（）
A. flow table
B. flow label
C. rout table
D. Tag table
在标准正态分布曲线下，正、负1个标准差范围内的面积占曲线下总面积的 ( )。
A．25.00%
B．34.13%
C．50.00%
D．68.26%
