Facebook CEO Mark Zuckerberg answered more than 600 questions during 10 hours of testimony, but what did we learn? Ali Velshi breaks down the headlines, and speaks with former Facebook operations manager Sandy Parakilas, who was responsible for privacy policies, to get an insider’s perspective on the platform’s data privacy issues. Ali also speaks with Noam Cohen, author of “The Know-It-Alls,” about Zuckerberg’s appearance before Congress and what’s next for the social media giant.