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Practice quizzes / Iowa CDL Combination Vehicles Test Practice Questions - Iowa Commercial Driver License Combination Vehicles Test Exam / Question 106292
Practice question

If trailer wheels lock and the trailer swings, what should you do?

  1. Set parking brakes
  2. Accelerate sharply
  3. Release the brakes to regain traction
  4. Apply the hand valve harder

Answer: C — Release the brakes to regain traction

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

Practice more: Iowa CDL Combination Vehicles Test Practice Questions - Iowa Commercial Driver License Combination Vehicles Test Exam →
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