Be careful what you post online.That’s one of the things Warren County High School junior Emma Mullican learned yesterday during Bologna Day in Nashville.“I thought things you posted on Snapchat were only there for 10 seconds, but the TBI director said they’re actually there forever,” said Mullican referring to a speech from TBI director Mark Gwyn, a McMinnville native. “He also talked about being careful when you’re talking to people online and he mentioned the 12-year-old girl who was abducted and killed by a guy who wanted to be a rocket scientist. You have to watch out for everybody.”Bologna Day serves as a day where local residents can mingle with their state representatives on Capitol Hill.