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Practice quizzes / LA CDL Combination Practice Questions - Louisiana CDL Combination Vehicles Test Exam / Question 115248
Practice question

What is the electrical line between tractor and trailer for?

  1. Charging trailer air tanks
  2. Holding up the landing gear
  3. Trailer lights and electrical equipment
  4. Mechanically locking the fifth wheel

Answer: C — Trailer lights and electrical equipment

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

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