Q
28. You are driving a combination vehicle when the trailer breaks away, pulling apart both air lines. You would expect the trailer brakes to come on and:
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AThe trailer supply valve to stay open.
BThe tractor to lose all air pressure.
CThe tractor protection valve to close.
Detailed Explanation
The correct answer is "The tractor protection valve to close.". This is based on federal CDL regulations and safety standards.
Correct Answer: The tractor protection valve to close.
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