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Air Brakes #1
Practice Test
Active Practice Session
Air Brakes #1
Question 5 of 25
20% complete
Question 5
The truck protection valve ________.
A
Supplies the braking system with air.
B
Automatically closes if the air supply falls below a particular threshold.
C
Can be closed by applying the parking brakes.
D
All of the above
Select an answer to continue.
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