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Air Brakes
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Doubles and Triples
Tanker Vehicles
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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 Practice Test
Question 1 of 3
Why is it a good idea to lock the glad hands together when not pulling a trailer?
A
Saves wear on the dummy coupler
B
Maintains air tank pressure by keeping air from escaping
C
Keeps water and dirt out of the lines
D
All of these are true
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