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Combination Vehicles #1
Practice Test
Active Practice Session
Combination Vehicles #1
Question 1 of 20
5% complete
Question 1
After you hook up the air lines, but before you back up under the trailer, you should:
A
Disconnect the electrical line.
B
Check the tire pressure on the trailer.
C
Supply air to the trailer system, then pull out the air supply knob.
Select an answer to continue.
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