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Class A CDL Practice Test #1
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What is the purpose of the emergency air supply line?


This line carries air to the tractor air tanks and controls the service brakes on combination vehicles.

This line carries air to the trailer air tanks and controls the service brakes on combination vehicles.

This line carries air to the trailer air tanks and controls the emergency brakes on combination vehicles.

This line carries air to the tractor air tanks and controls the emergency brakes on combination vehicles.

None of the above.



Class A Commercial Driver’s License

You will need a “Class A” commercial driver’s license if you plan to drive any combination of vehicles which have a gross combination weight rating or gross combination weight of 26,001 pounds or more, whichever is greater, including a possible towed unit or units with a gross vehicle weight rating or gross vehicle weight of more than 10,000 pounds, whichever is greater.

Source: Federal Motor Carrier Safety Administration.


 

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