Two St. Louis startups debut on the New York Stock Exchange. They're called 'unicorns' after having grown to more-than a billion dollar valuations. Food tech company Benson Hill's CEO Matt Crisp joins us. We'll hear from BioSTL's Donn Rubin about their investment support for the company. Online learning firm Nerdy CEO Chuck Cohn calls after ringing the bell. Greater St. Louis Inc.'s Jason Hall puts it all in perspective.