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Practice quizzes / DC CDL General Knowledge Practice Questions - District of Columbia Commercial Driver License General Knowledge Test Exam / Question 77514
Practice question

How long before operating a CMV is alcohol use prohibited under federal rules?

  1. Within 4 hours
  2. Within 30 minutes
  3. Only while the vehicle is moving
  4. Only after a crash

Answer: A — Within 4 hours

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

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