Uh oh! Wolfram|Alpha doesn't run without JavaScript.
Please enable JavaScript. If you don't know how, you can find instructions
here
.
Once you've done that, refresh this page to start using Wolfram|Alpha.
Bg视讯注册（网址:NBA88.COM）Bg视讯注册_Bg视讯注册_Bg视讯注册_qIyq55I7
Natural Language
Math Input
Extended Keyboard
Examples
Upload
Random
