guest Moderator 管理成员 注册 2002-10-07 消息 402,576 荣誉分数 76 声望点数 228 2019-01-02 #1 When Barbara Havrot retired from teaching in Ottawa, she took her passion for math into the online world of YouTube, where she now uploads videos of herself teaching everything from trigonometry to calculus. 查看原文...
When Barbara Havrot retired from teaching in Ottawa, she took her passion for math into the online world of YouTube, where she now uploads videos of herself teaching everything from trigonometry to calculus. 查看原文...
