FREE CDL Class B Driving Test Online | District Of Columbia 2024 Page 2 of 7
Train for FREE online with our District Of Columbia class B license test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a DC CDL class B permit in 2021, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that CDL class B requirements may vary from state to state.
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8 . If driving in a foggy area, you should not:
Turn on your four-way flashers.
It is safest not to drive in foggy areas. However, if you must drive through fog, you should slow down, use your low beam headlights and fog lights, and turn on your four-way flashers.
9 . What can change the height of a vehicle?
Number of windows
The added weight of a heavy load will make a vehicle sit lower than usual. A vehicle will often be taller when carrying a light load than when carrying a heavy load. If your vehicle fits under an overpass while carrying a full load, it is not guaranteed that it will fit under the same overpass if it is empty.
10 . Most CDL holders have ____ licenses.
Non-exempted
Most CDL holders who drive CMVs in interstate commerce are non-excepted interstate commerce drivers.
11 . A low air pressure warning signal should activate:
When tank pressure falls below 5 psi.
In an air brake system, a low air pressure warning signal must come on if air pressure in the tanks falls below 60 psi. This warning signal may come in the form of a light, a buzzer, or a wig wag.
12 . Belts in the engine compartment should be:
Easy to slide off.
When inspecting your vehicle's engine, check the belts for tightness and excessive wear. The amount of "give" that is safe for each belt in a given engine will vary, so learn what is appropriate for your vehicle.
13 . Which part of the truck is the air compressor connected to?
The door latch
In an air brake system, the air compressor is connected to the engine through gears or a v-belt.
14 . Of the following, which is not a way to prevent drowsiness during a trip?
Avoiding medications that may cause drowsiness
