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Practice quizzes / Michigan CDL Doubles Triples Practice Questions - Michigan CDL Doubles and Triples Endorsement Test Exam / Question 127250
Practice question

Why must air reach all the way to the last trailer?

  1. All trailer brakes need air to operate properly
  2. Only the tractor brakes matter
  3. Air powers the GPS
  4. It inflates the spare tire automatically

Answer: A — All trailer brakes need air to operate properly

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

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