Columbia University's Columbia Plus: free courses now available — AI for Business; Machine Learning for Environmental Engineering; The Art of Opinion Writing (code: WRITEFREE); Intro to Financial Engineering & Risk Management; Protecting Children in Humanitarian Settings; The Civil War & Reconstruction (1850–1861); Wage Work for Women Citizens (1870–1920). https://plus.columbia.edu/course-catalog #ColumbiaPlus #FreeCourse #OnlineLearning