North Dakota CDL Practice Test: Double and Triples - Test 3 2020(From the 2020 North Dakota CDL Handbook)
|Number of tests:||26|
|Number of questions:||30|
Directions: To obtain this endorsement for pulling two or three trailers, applicants must pass a 15-question test. And to pass the test, applicants must score at least 80%. Test questions are from the North Dakota Commercial Driver Handbook. The Double/Triple trailers endorsement can be used with the Class A CDL. If you need additional information, please contact your local DMV office. You can find your nearest DMV office at North Dakota DMV locations.
1. What are hose couplers?
2. Usually, a fully charged air system has _______ psi.
3. The tractor protection valve ______.
4. The pressure in the service line indicates ______.
5. Trailers that do not have spring brakes have emergency brakes, which work from ________.
6. The spring brakes come on when the air pressure drops into what range _________.