HOUSTON -- All their assigned duties were completed and final precautionary tests had turned up no problems Sunday, leaving weather the only question facing the astronauts on the space shuttle Discovery as they looked forward to a return to Earth. Mission Control on Sunday gave the shuttle crew permission to try for a landing Monday at the Kennedy Space Center in Florida, clearing all lingering technical questions on the shuttle heat shield and the system that provides hydraulic power for landing. "We feel very confident that Discovery is safe to come home," landing director Steve Stich said in a news...