1.introduction to ratio比例 上传者:lfcacademy 01:16 3.ratio as fraction in simplest form比例转化为最简单的分数 上传者:lfcacademy 01:20 2.understanding proportion理解比率 上传者:lfcacademy 播单创建者 lfcacademy 署名-非商业性使用-相同方式共享 (by-nc-sa) ...
Khan Academy GRE Prep Khan Academy’s clear and in-depth videos can be a useful resource for your GRE studying, particularly for the Quantitative Reasoning section of the test. You can easily find videos that relate to the specific topic you’re trying to learn more about. Khan Academy GRE...
Of course, the big news this week is that MIT and Harvard announced that they're joining forces to offer free online courses starting next fall. We gave you the scoop on that yesterday. Open Culture, openculture.com