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Practice quizzes / Iowa CDL Combination Vehicles Test Practice Questions - Iowa Commercial Driver License Combination Vehicles Test Exam / Question 106349
Practice question

How do you verify air flows to the rear?

  1. Check radio
  2. Lower landing gear
  3. Turn headlights on
  4. Open rear emergency and service valves after charging and listen for air

Answer: D — Open rear emergency and service valves after charging and listen for air

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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