How far away should you be following another vehicle based on your speed?

• 1 car length for every 10 KM/H
• 1 car length for every 25 KM/H
• 1 car length for every 20 KM/H
• 1 car length for every 15 KM/H
  Explanation:

  "1 car length for every 15 KM/H"