Historian and Oxford University professor Timothy Garton Ash argues that free speech is essential to our survival in the digital age. The HBO film "Class Divide," directed by Marc Levin, explores the effects of gentrification and rising economic inequality in a NYC neighborhood. Nobu Adilman and Daveed Goldman, the creative directors of Toronto-based singing group, “Choir! Choir! Choir!” talk about their non-traditional, inclusive approach to choral singing. Aviation journalist Christine Negroni investigates the causes of historical and modern airplane crashes.