0.00/10 2016-06-01 48 minutes.HDIn this episode, a high tech submarine allows for better underwater exploration; an average nose can sense 1,200 flavors; mysterious stains on St. Louis’ Gateway Arch prompt a tricky testing procedure; and the U.S. military is turning to microgrids to keep its power reliable and secure.An: 2016Studio: PBSPays: United States of America