It is 10:30 PM. Your snowmobile is out of gas and you are three miles due south of a major highway. The...?

It is 10:30 PM. Your snowmobile is out of gas and you are three miles dues south of a major highway. The nearest service station is on the highway 6 miles east and it closes at midnight. You can walk 4 mph on the highway but only 3 mph through the snowy fields. Determine the minimum amount of time required for you to make it to the service station. Will you get there before it closes?