 A federal safety regulator is telling parents to talk to kids about weed and driving. NTSB Chair Jennifer Homendy is urging parents to warn their teenagers about the dangers of driving after using marijuana. She cites a crash in Tishomingo, Oklahoma, that killed six high school girls two years ago. The teens were riding in a tiny Chevy Spark hatchback, which collided with a gravel-hauling semi-truck. Toxicology reports found marijuana