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Practice quizzes / NJ CDL Combination Practice Questions - New Jersey CDL Combination Vehicles Test Exam / Question 147949
Practice question

What does pushing in the red trailer air supply control do?

  1. Supplies air to the trailer
  2. Use only the trailer hand valve
  3. Ignore it if the tractor feels normal
  4. Raise the landing gear halfway

Answer: A — Supplies air to the trailer

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

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