🔗Missouri Combination Vehicles — Question 19 of 20
You have pushed the trailer air supply valve. You should not back a tractor under a trailer until the whole air system is:
Missouri CDL Combination Vehicles Test Info
Questions on Exam
20
Passing Score
80%
Time Limit
Typically 30 minutes; varies by testing location
Age Requirements
Intrastate: 18+ · Interstate: 21+
Missouri DOR
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