Q
79. What is the emergency air line for?
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Aa. To engage the front brakes of the tractor in case of an emergency.
Bb. To engage the trailer brakes in case of air pressure loss.
Cc. To have extra air pressure in case you need it.
Detailed Explanation
The correct answer is "b. To engage the trailer brakes in case of air pressure loss.". This is based on federal CDL regulations and safety standards.
Correct Answer: b. To engage the trailer brakes in case of air pressure loss.
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