You have been driving your coach for 4 hours without a qualifying break. How much driving remains before a break is required?

1. 1 hour, because daily driving is 9 hours and you have used 4
2. 30 minutes, because 4.5 hours minus 4 hours leaves 0.5 hours
3. 45 minutes, matching the coming break
4. 2 hours, if you intend to use a 10-hour day