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Air Brakes
Combination Vehicles
Doubles and Triples
Tanker Vehicles
Hazardous Materials
Transporting Passengers
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CDL Practice Test
General Knowledge
Air Brakes
Combination Vehicles
Doubles and Triples
Tanker Vehicles
Hazardous Materials
Transporting Passengers
CDL Combination Vehicles Practice Test
Question 1 of 3
How would a driver supply air to trailer air tanks?
A
Activate the air generator
B
Push in the trailer air supply valve
C
Activate the service line
D
Pull out the trailer air supply valve
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