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Practice quizzes / Iowa CDL Combination Vehicles Test Practice Questions - Iowa Commercial Driver License Combination Vehicles Test Exam / Question 106289
Practice question

Above 40 mph, what is added to the 1-second-per-10-feet following-distance rule?

  1. No extra time
  2. Five extra seconds per trailer
  3. A fixed two-second rule
  4. One extra second

Answer: D — One extra second

The correct answer is shown above. Try the full quiz for additional practice.

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