Final answer:
The following distance should be at least 3-4 seconds or 3-4 times the length of your car.
Step-by-step explanation:
The following distance when driving between 46-70 mph on flat, dry pavement should be at least 3-4 seconds.
This means that you should keep a distance of 3-4 times the length of your car between you and the car in front of you.
For example, if your car is 4 meters long, then you should keep a distance of 12-16 meters between you and the car in front of you.