What is Oorah? The classic trivia game show Jeopardy had a motivated night on Thursday with a second-round category titled “The United States Marines.” Contestants Rebecca Rider, Brian Daner, and Tom Carroll could have used some time in history and heritage training; of the five questions in the category, they got two wrong. Maybe they need more practice: a search of the fan-curated episode archive shows that while a category on Marine biology pops up about once a year, the last time the Corps got a dedicated category was 2009, when the National Museum of the Marine Corps was featured.   See…