Now Playing: 03-27-12 Marketplace

Health reporter Gregory Warner reports on the second day of Supreme Court hearings on the health care law. Why did Justices use the word 'broccoli' to describe the individual mandate? The Obama administration proposed the first federal limits on greenhouse gas emissions from new power plants. We hear about the new Facebook app EnemyGraph, which shows what you dislike. And special correspondent David Brancaccio continues his series, Robots Ate My Job.