Q
72. What is a tractor jackknife?
Combination Vehiclesmedium
Aa. When you lock up the drive tires on the trailer and the trailer spins out sideways as the tractor continues to push forward.
Bb. When you lock up the drive tires on the tractor and the tractor spins out sideways as the trailer continues to push forward.
Cc. Neither of these answers are correct.
Detailed Explanation
The correct answer is "b. When you lock up the drive tires on the tractor and the tractor spins out sideways as the trailer continues to push forward.". This is based on federal CDL regulations and safety standards.
Correct Answer: b. When you lock up the drive tires on the tractor and the tractor spins out sideways as the trailer continues to push forward.
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