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Practice quizzes / QLD Heavy Vehicle Knowledge Test Practice Questions - Queensland Class LR MR HR HC MC Heavy Vehicle Road Rules Knowledge Test Exam / Question 169499
Practice question

What colour is typically used for the service (control) air line on Australian heavy vehicle couplings?

  1. Yellow
  2. Red
  3. Black
  4. Orange

Answer: A — Yellow

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

Practice more: QLD Heavy Vehicle Knowledge Test Practice Questions - Queensland Class LR MR HR HC MC Heavy Vehicle Road Rules Knowledge Test Exam →
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