Under Article 68 of the Road Traffic Safety Law and Article 60 of the Implementing Regulations, when a vehicle breaks down on an ordinary road versus an expressway, at what distances must the warning triangle (警告标志) be placed behind the vehicle?

1. Ordinary road: 50–100 meters; Expressway: at least 150 meters (普通路50-100米，高速路150米以外)
2. Ordinary road: 20–50 meters; Expressway: 80–100 meters
3. Ordinary road: 100–150 meters; Expressway: at least 200 meters
4. Ordinary road: 30–50 meters; Expressway: at least 50 meters