Picture yourself in the blue car, driving behind the red one. At a minimum, how much space should you leave?
Correct answer: One car length for every 10 mph, or a 3-second gap.
Answer options
AOne car length for every 10 mph, or a 3-second gap Correct
BOne car length for every 20 mph, or a 1.5-second gap
COne car length for every 30 mph, or a 1-second gap
Why
Keeping at least one car length for each 10 mph, or a gap of 3 seconds or more, gives you time to spot trouble ahead and brake. The other choices leave much less room than either measure calls for, and rain, fog, or heavy traffic call for even more space.