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Practice quizzes / Washington CDL Combination Practice Questions - Washington CDL Combination Vehicles Test Exam / Question 201502
Practice question

After coupling and connecting the air lines, you should next:

  1. Drive forward immediately
  2. Lower the landing gear
  3. Charge the trailer air system, then test for leaks before driving
  4. Pull the trailer air supply knob

Answer: C — Charge the trailer air system, then test for leaks before driving

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

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