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Practice quizzes / VT CDL General Knowledge Practice Questions - Vermont Commercial Driver License General Knowledge Test Exam / Question 200373
Practice question

What is the purpose of the air compressor in an air brake system?

  1. To pump air into the air storage tanks
  2. To release the parking brakes
  3. To cool the brake drums
  4. To lubricate the brake shoes

Answer: A — To pump air into the air storage tanks

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

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