CDL knowledge test

General Knowledge practice test

Every CDL applicant takes this one, whatever the class. It covers vehicle inspection, safe driving, space and speed management, cargo weight, hours of service, and emergencies.

376 questions available. A study sitting draws 50, and the App practice target: 80%; this is not an official test score. Your state sets the real test length.

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General Knowledge questions with answers

Every question below carries the answer, the reason, and the section of the FMCSA CDL Manual or 49 CFR it comes from. Nothing here is a recalled exam question.

At what blood alcohol concentration does the federal CDL disqualification threshold begin for a driver operating a commercial motor vehicle that requires a CDL?
- A0.04%Correct
- B0.08%
- C0.02%
- D0.00%
The federal CDL disqualification threshold begins at 0.04% BAC when operating a commercial motor vehicle that requires a CDL. This is not permission to drive with a lower BAC. Separate on-duty alcohol prohibitions apply. Do not confuse the disqualification threshold with an amount that is safe or allowed before driving.
49 CFR § 383.51 · Table 1, item (3): alcohol concentration of 0.04 or greater while operating a CMV · verified 2026-09-08
When should you downshift to control speed on a long downgrade?
- AAfter gaining too much speed
- BBefore starting down the hillCorrect
- CHalfway down the hill
- DAt the bottom of the hill
Select a lower gear before starting down a long downgrade to use engine braking effectively and preserve your service brakes.
FMCSA Commercial Driver's License Manual · Section 2.16 — Mountain Driving: select a lower gear before starting down a long downgrade · verified 2026-09-08
What is the minimum tread depth in a major groove for a front tire on a bus, truck, or truck tractor?
- A2/32 inch
- B4/32 inchCorrect
- C6/32 inch
- D8/32 inch
Federal rules require at least 4/32 inch tread depth in a major groove on the front tires of a bus, truck, or truck tractor. Other tires need at least 2/32 inch. This is a federal operating minimum; a state, carrier, or vehicle rule may be stricter.
eCFR 49 CFR 393.75 — Tires · 393.75(b) — Tread groove depth · verified 2026-09-07
The purpose of a pre-trip inspection is to:
- AIdentify problems that could cause a crash or breakdownCorrect
- BDocument mileage for the trip log
- CSatisfy DOT requirements only
- DCheck fuel levels
Before driving, the driver must be satisfied that the vehicle is in safe operating condition. Inspecting equipment helps find defects before they cause a crash or breakdown; it is more than a fuel check or paperwork task.
49 CFR § 396.13 · 396.13(a) safe operating condition before driving · verified 2026-09-07
According to the CDL manual, how often should you check your mirrors while driving?
- ARegularly, and more often in special situationsCorrect
- BOnly when changing lanes
- COnly when backing up
- DOnce at the start of each trip
The manual says to check your mirrors regularly and more often in special situations, to know where other vehicles are and whether they move into your blind spots.
FMCSA Commercial Driver License Manual (July 2014) · Section 2.4.2: Seeing to the Sides and Rear · verified 2026-09-25
If your commercial vehicle is hydroplaning, you should:
- ABrake firmly to slow down before the tires lose more grip
- BAccelerate gently so the drive tires cut through the water
- CRelease the accelerator, avoid braking, and keep the wheel straightCorrect
- DSteer sharply toward the shoulder to find a drier surface
When hydroplaning, release the accelerator and push in the clutch if it is safe; do not use the brakes, and keep the steering wheel straight until traction returns.
FMCSA Commercial Driver License Manual · Section 2.6.2: Hydroplaning · verified 2026-09-29
At speeds below 40 mph, what minimum following-distance rule applies to a commercial vehicle?
- AAt least one second per 10 feet of vehicle lengthCorrect
- B2 seconds, regardless of the vehicle's length
- C4 seconds
- D10 seconds
Follow the formula: one second for each 10 feet of vehicle length at speeds below 40 mph, plus one extra second above 40 mph.
FMCSA Commercial Driver License Manual · Section 2: Driving Safely — Following Distance · verified 2026-09-08
Before driving a commercial motor vehicle, what must the driver be satisfied about the cargo?
- AIt is properly distributed and adequately securedCorrect
- BIt is covered by a radio dispatch notice
- CIt is visible to the driver in every mirror
- DIt includes an extra set of tie-downs
Federal rules require the driver to be satisfied that cargo is properly distributed and adequately secured before driving a commercial motor vehicle.
49 CFR § 392.9 · Section 392.9(a): cargo properly distributed and adequately secured · verified 2026-09-08
What can result from too much weight on the steering axle?
- ABetter steering
- BHard steering and damage to steering axleCorrect
- CImproved fuel economy
- DSmoother ride
Too much weight on the steering axle makes steering difficult and can damage the steering axle.
FMCSA Commercial Driver License Manual · Section 3: Transporting Cargo Safely · verified 2026-09-08
You are driving a 40-foot vehicle at 35 mph. What is the minimum following distance you should maintain?
- A2 seconds
- B3 seconds
- C4 secondsCorrect
- D5 seconds
At speeds below 40 mph, use one second for each 10 feet of vehicle length. A 40-foot vehicle requires at least 4 seconds.
FMCSA Commercial Driver License Manual · Section 2: Driving Safely - Space Management · verified 2026-09-08
Under the FMCSA manual's basic model, before adding air-brake lag, which three distances make up stopping distance?
- APerception distance, reaction distance, braking distanceCorrect
- BSpeed, weight, road conditions
- CEye lead time, following distance, space cushion
- DTire tread, brake condition, vehicle weight
The basic model adds perception, reaction, and braking distance. For air-brake vehicles, the manual adds brake-lag distance as a fourth component.
FMCSA Commercial Driver's License Manual (July 2014 edition) · Sections 2.6.1 and 5.4.4: basic stopping-distance model and added air-brake lag · verified 2026-09-20
If your CMV stops on the shoulder of a divided or one-way highway, where should you place warning devices?
- A10 feet, 50 feet, and 100 feet behind the vehicle
- BOne within 10 feet of the rear, plus others at 100 and 200 feet toward approaching trafficCorrect
- C50 feet, 100 feet, and 200 feet behind the vehicle
- D100 feet, 200 feet, and 300 feet behind the vehicle
On a divided or one-way highway, place one warning device at the traffic side within 10 feet of the rear. Place the other two at 100 and 200 feet toward approaching traffic in the lane or shoulder your vehicle occupies.
49 CFR § 392.22 · § 392.22(b)(2)(v) — Divided or one-way highway placement · verified 2026-09-19
According to federal regulations, you must inspect your cargo within the first ____ miles of your trip.
- A75 miles
- B50 milesCorrect
- C25 miles
- D100 miles
Federal rules require cargo securement devices to be reexamined within the first 50 miles. They must then be reexamined and adjusted as needed after 3 hours of driving or 150 miles, whichever occurs first, and after a change of duty status.
49 CFR § 392.9 · Section 392.9(b): reexamination of cargo securement devices · verified 2026-09-08
What does the federal bridge formula allow when a vehicle's axle groups are spaced farther apart?
- AOnly applies to bridges over water
- BPermits heavier loads on trucks with axles closer together
- CIs the same for all states
- DPermits heavier loads on trucks with axles farther apartCorrect
The bridge formula permits heavier weights when axles are spaced farther apart to distribute weight over more road surface.
FMCSA Commercial Driver License Manual · Section 3: Transporting Cargo Safely - Weight and Balance · verified 2026-09-08
Name two situations where you should downshift:
- ABefore starting down a hill and before entering a curveCorrect
- BWhile going up a hill and while on straight roads
- CAfter stopping and after making a turn
- DWhile accelerating and while hydroplaning
Downshift before starting down a hill (for engine braking) and before entering a curve (for better control).
FMCSA Commercial Driver License Manual · Section 2: Driving Safely - Shifting Gears · verified 2026-09-08
Retarders help slow the vehicle, but they:
- AShould always be used in wet weather
- BCan cause the drive wheels to skid when traction is poorCorrect
- CIncrease fuel consumption
- DAre only effective at high speeds
Retarders can cause drive wheels to skid when traction is reduced (wet, icy, or snowy conditions). Turn them off in poor conditions.
FMCSA Commercial Driver License Manual · Section 2: Driving Safely - Retarders · verified 2026-09-08
What is the proper way to make a right turn in a commercial vehicle?
- ATurn wide before the turn
- BStay tight to the curb throughout
- CTurn wide as you complete the turnCorrect
- DSpeed up through the turn
Keep your rear wheels close to the curb during initial turn, then complete the turn by swinging wide to accommodate off-tracking.
FMCSA Commercial Driver License Manual · Section 2: Driving Safely - Turns · verified 2026-09-08
You are driving a 50-foot truck at 50 mph. The safe following distance is at least:
- A6 secondsCorrect
- B5 seconds
- C7 seconds
- D8 seconds
At 50 mph (above 40), add 1 second to base formula: 5 seconds for 50 feet + 1 second for speed = 6 seconds minimum.
FMCSA Commercial Driver License Manual · Section 2: Driving Safely - Space Management · verified 2026-09-08
During a pre-trip, you find a vehicle condition likely to cause an accident or breakdown. What should you do?
- ADrive carefully to a repair shop
- BDo not drive until it is repairedCorrect
- CReport it but continue driving
- DComplete your route first
A motor vehicle must not be operated in a condition likely to cause an accident or breakdown. The rule has a narrow exception for an unsafe condition discovered while operating on a highway, which does not make a pre-trip departure safe.
eCFR 49 CFR 396.7 · 49 CFR 396.7(a): unsafe operations forbidden · verified 2026-09-08
If you have a tire failure while driving, you should:
- AApply the service brakes hard immediately to stop
- BHold the wheel firmly, stay off the brakes, let it slowCorrect
- CTurn the steering wheel sharply toward the shoulder
- DSpeed up briefly to maintain control of the vehicle
Stay off the brakes and accelerator, hold the steering wheel firmly, and let the vehicle slow down on its own before braking gently.
FMCSA Commercial Driver License Manual · Section 2: Emergencies · verified 2026-09-08

What this test is drawn from

11.2 External Inspection (Drive Shaft)
14-hour limit
2.1.3 What to Look For (steering)
2.14.2 Driving (hot weather)
2.16.2; 2.17.3
2.16.4 Proper Braking Technique
2.17.2
2.20.1 Protect the Area
2.4.2 Seeing to the Sides and Rear (Mirror Adjustment)
2.6.6; 2.16.2–2.16.4
2.7.4 Space Overhead
23 CFR § 658.17: Vehicle weight limitations
3.2.4 — Balance the Weight
30-Minute Driving Break
34-hour restart
34-hour restart provision
383.5 tank vehicle definition; Oregon section 8 introduction
392.10(a) listed vehicles and (b) exceptions
392.11 slowing and clear-course requirement
392.7(a) Equipment, inspection and use
392.9(b)(2) first 50 miles; (b)(4) exceptions
393.60(c) — Windshield condition
393.60(c) — Windshield condition and exceptions
393.75(a) — Tire condition
393.75(b) — Front-tire tread depth
393.75(b) — Tread groove depth
393.75(c)
393.75(c) — Tread groove depth
393.95(a) and (f); paragraph (b) reserved after 91 FR 7877, effective 2026-04-20
393.95(a), (f), and (g); paragraph (b) reserved
395.2 (Electronic logging device)
395.3(a)(1)
395.3(a)(2) 14-hour period; (a)(3) driving time
395.3(c)
395.8(e)(1)
396.11(a)(1) minimum parts and accessories
396.13(a) safe operating condition before driving
396.17(a) — Periodic inspection
396.3(a)(1) — Bus emergency exits and marking lights
396.9(c) — Out-of-service order
396.9(d) — Certification of correction
49 CFR 383.51: Disqualification for major offenses
49 CFR 383.93(c): Tank vehicle and hazardous materials (X) endorsement
49 CFR 393.95(a)(1)-(4)
49 CFR 396.13; FMCSA Manual Section 2.1.1: Vehicle inspection before driving
49 CFR 396.7(a): unsafe operations forbidden
49 CFR 397.67: Motor carrier responsibility for hazardous-material routing
49 CFR § 392.5(a)(2), (c) — on-duty alcohol prohibition and 24-hour out-of-service order
5.3.3 — Test Low Pressure Warning Signal
6.2.4 Air-lines; 6.2.5 Hose Couplers; 6.4.1 Coupling; 6.4.2 Uncoupling
6.5.1 Combination walk-around inspection; 6.5.2 brake checks
60/70-Hour Limit
60/70-hour limit
Adverse driving conditions
Assistance in investigations and special studies
Availability for post-accident testing
Brake adjustment
Cargo balance
Cargo securement - tiedowns
Cargo securement inspection intervals
Coercion prohibited
Commercial Motor Vehicle Requirements
Commercial learner permit holder supervision requirements
Commercial motor vehicle groups - Group C
Complaint of coercion
Complaint of harassment
Contents of a coercion complaint
Controlled substance use
Definition of coerce or coercion
Definition of driving
Definitions — Gross combination weight rating
Definitions — Gross combination weight rating (GCWR)
Disqualification - alcohol and controlled substances
Disqualification - out-of-service order
Divided or one-way roads
Driver application and certification procedures - CDL transfer after domicile change
Driver inspection
Driver vehicle inspection report(s)
Driving Safely
ELD malfunctions and data diagnostic events
ELD record submissions and certification
ELD requirement
ELDT applicability: first H endorsement before knowledge test
Electronic logging device and hours of service records
Emergency Maneuvers — Brake Failure
Emergency Maneuvers — Downgrade Braking
Emergency Maneuvers — Fire Response
Emergency Maneuvers — Hydroplaning
Emergency Maneuvers — Jackknife Prevention
Emergency Maneuvers — Vehicle Fire
Emergency signals; stopped commercial motor vehicles
Employee protections
Exhaust discharge location
Exhaust system repairs
Exhaust systems
FULL INSPECTION: Level I / North American Standard (NAS)
Falsifying logs
General Knowledge — 60-Hour Rule
General Knowledge — ABS
General Knowledge — Air Lines
General Knowledge — Alcohol and Drug Rules
General Knowledge — Brake Fade
General Knowledge — Braking Techniques
General Knowledge — Cargo Securement
General Knowledge — Crash Avoidance
General Knowledge — Disqualifying Offenses
General Knowledge — Distracted Driving
General Knowledge — Driver Reporting Responsibilities
General Knowledge — Engine Braking
General Knowledge — Fire Extinguisher Types
General Knowledge — Fuel Economy
General Knowledge — Hours of Service Overview
General Knowledge — Night Driving
General Knowledge — No-Zones
General Knowledge — Physical Qualifications
General Knowledge — Retarder Cautions
General Knowledge — Retarders
General Knowledge — Serious Traffic Violations
General Knowledge — Speed and Braking
General Knowledge — Steering Failure
General Knowledge — Traffic Control Signals
General Knowledge — Vision Requirements
General Knowledge — Weather Hazards
General qualifications of drivers
Hazardous conditions; extreme caution
Hearing standards
Hills, curves, and obstructions
Hours of Service
Hours of Service — 14-Hour Rule
Hours of Service — Adverse Conditions
Hours of Service — Enforcement
Hours of Service — Passenger Carrier 70-Hour
Hours of Service — Passenger Carrier Rules
Hours of Service — Record Retention
Hours of Service — Recordkeeping
Hours of Service — Short-Haul Exemption
Hours-of-service overview: on-duty limits and rest periods
Ill or fatigued operator
In a vehicle during a winter storm (Stay in the vehicle; run the motor)
Inspection of cargo and securement devices
Inspection of motor vehicles in operation
Instructions and documents
Interruption of driving periods
Introduction to CDL
Lifetime CDL disqualification rules
Maximum driving time for property-carrying vehicles
Medical examination; certificate of physical examination
Medical examiner's certificate
Motor carrier disposition of inspection reports
No person may have more than one license
Notification to employers of a violation
On-duty use
One driver license and state-issued CDL requirements
Out-of-service sticker removal
Periodic inspection of combination vehicles
Personnel authorized to perform inspections
Persons who must be medically examined and certified
Physical qualifications - vision
Physical qualifications for drivers
Placement of warning devices
Post-accident controlled substances testing
Post-accident testing
Pre-duty use
Pre-employment testing
Protected refusals to operate
Re-examination after impairment
Recognising impairment
Record of duty status
Record retention
Reexamination during transportation
Removal from safety-sensitive function
Restart provisions
Retention period for reports
Road-sharing guidance: commercial vehicle blind spots
Section 11.2.3 - Brakes (Brake Chambers)
Section 11.2.4: Tires
Section 11.5 - Out-Of-Service Defects
Section 2 - Driving Safely
Section 2 - Entering and Exiting Highways
Section 2 - Maneuvering in Restricted Areas
Section 2 - Multi-Speed Dual-Range Transmissions
Section 2 - Right Turns
Section 2 - Selecting a Safe Speed and Gear
Section 2 - Shifting Gears
Section 2 - Shifting Patterns and Procedures
Section 2 - Staying Alert and Fit to Drive
Section 2 - Turning
Section 2 - When to Shift
Section 2 - When to Shift Up
Section 2.1 - Vehicle Inspection Overview
Section 2.1 — Vehicle Inspection Guide; brake components
Section 2.1.2 - Wheels And Rims
Section 2.1.3 - Tires - Defects
Section 2.1.4 - Steering System Check
Section 2.1.5 - Suspension System Check
Section 2.1.6 - Exhaust System Check
Section 2.1.6: Suspension system defects
Section 2.10 - Seeing Hazards - Work Zones
Section 2.11 - Driving At Night
Section 2.11.4 — Night Driving; Oregon Manual § 2.11.4 cross-check
Section 2.13 - Railroad Crossings
Section 2.14 - Escape Ramps
Section 2.14 - Mountain Driving - Escape Ramps
Section 2.14 - Mountain Driving - Selecting A Safe Gear
Section 2.15 - Railroad-highway Crossings
Section 2.15 — Railroad-highway Crossings; Oregon Manual § 2.15.5 cross-check
Section 2.16 - Hydroplaning
Section 2.16 - Mountain Driving
Section 2.16 - Wet Roads
Section 2.16 — Mountain Driving: select a lower gear before starting down a long downgrade
Section 2.16.2 and 2.16.4 — Select the Right Gear before Starting Down the Grade; Proper Braking Technique
Section 2.16: Mountain driving
Section 2.17 - How To Avoid Distractions
Section 2.17.3: Brake failure (Brake failure on downgrades; escape ramps)
Section 2.17.4: Tire Failure
Section 2.18 - Hazardous Materials Awareness
Section 2.18.6 - Braking with ABS
Section 2.19 - Brake Failure On A Downgrade
Section 2.19 - Leaving The Road To Avoid A Crash
Section 2.19 - Skid Control - Drive-Wheel Skid
Section 2.19 - Tire Failure - Front
Section 2.19 - Using A Fire Extinguisher
Section 2.1: Vehicle Inspection (emergency equipment)
Section 2.1: Vehicle Inspection (steering)
Section 2.2 - Backing Safely
Section 2.2 - Communicating - Signaling
Section 2.2 - Communicating - Stopping On The Road
Section 2.2.1: Accelerating without rolling back
Section 2.21 - Accident Procedures
Section 2.21.3 - Fire Fighting
Section 2.3 - Turning - Off-Tracking
Section 2.3.4: Retarders
Section 2.4 - Backing Safely
Section 2.4.2: Seeing to the Sides and Rear
Section 2.5 - Communicating
Section 2.5 - Controlling Speed - Hazard Lights
Section 2.5 - Seeing - Use Of Mirrors
Section 2.5.1 - Signal Your Intentions (warning devices, two-lane road)
Section 2.5.1: Signal Your Intentions
Section 2.6 - Controlling Speed
Section 2.6 - Seeing Hazards
Section 2.6 - Standing Water And Hydroplaning
Section 2.6 - Stopping Distance
Section 2.6.1: Stopping Distance
Section 2.6.2: Hydroplaning
Section 2.7 - Managing Space
Section 2.7 - Matching Speed To Traction
Section 2.7 - Speed And Distance Ahead
Section 2.7 - Speed On Downgrades
Section 2.7.1: Space Ahead
Section 2.7.3: Space to the sides (Traveling next to others)
Section 2.7.6: Space for Turns
Section 2.7.6: Space for Turns / Strong Winds (Section 2 Driving Safely)
Section 2.8 - Seeing - Looking Ahead
Section 2.8 - Seeing Hazards
Section 2.9 - Managing Space - Behind
Section 2.9 - Managing Space - Overhead
Section 2.9 - Managing Space - Space Ahead
Section 2.9 - Managing Space - To The Sides
Section 2: Driving Safely
Section 2: Driving Safely - Retarders
Section 2: Driving Safely - Shifting Gears
Section 2: Driving Safely - Space Management
Section 2: Driving Safely - Turns
Section 2: Driving Safely — Following Distance
Section 2: Emergencies
Section 3 - Transporting Cargo Safely
Section 3.1 - Axle Weight And Balance
Section 3.1 - Balancing The Load Side To Side
Section 3.1 - Center Of Gravity
Section 3.1 - Legal Weight Limits
Section 3.1 - Weight And Balance Definitions
Section 3.2 - Inspecting Cargo En Route
Section 3.2 - Securing Cargo - Blocking And Bracing
Section 383.91(a): Group A
Section 383.91(b): Group B
Section 383.93(b): Passenger endorsement
Section 383.93(c): Hazardous materials endorsement
Section 383.93(e): Double/triple trailers endorsement
Section 390.15: Assistance in investigations and special reports
Section 392.9(a): cargo properly distributed and adequately secured
Section 392.9(b): reexamination of cargo securement devices
Section 393.100: Which types of cargo must be immobilized or secured
Section 3: Transporting Cargo Safely
Section 3: Transporting Cargo Safely - Weight and Balance
Section 5.1.2 and 5.3.3 — Compressor buildup and final air-brake check
Section 5.1.2 — Air Compressor; typical dual-air system buildup
Section 5.3.2: Check Slack Adjusters on S-cam Brakes
Section 5.4.4: air-brake lag and total stopping distance
Section 6.1.5: Prevent trailer skids
Section 6.5.1: Coupling system inspection
Sections 2.19.1 Drive-wheel skids and 2.19.2 Correcting a drive-wheel braking skid
Sections 2.6.1 and 5.4.4: basic stopping-distance model and added air-brake lag
Serious traffic violations
Sleeper Berth Provision
Sleeper berth provision
Slow Down; Keep Your Distance; Pay Attention
State and local laws, ordinances, and regulations
Suspension systems
TIP #2: Enter a Curve Slowly; TIP #3: Reduce Your Speed Before Entering an Exit/Entrance Ramp
Table 1, item (3): alcohol concentration of 0.04 or greater while operating a CMV
Timing of post-accident tests
Unsafe operations forbidden
Use following an accident
Use of seat belts
Using a hand-held mobile telephone
Vehicle Inspection — Landing Gear
Vehicles declared out-of-service
Vision standards
Weekly on-duty limits
Weight Distribution
Weight Distribution — Shifting Loads
Weight — Axle Limits
Weight — Bridge Formula
Weight — Cargo Securement
Weight — Tandem Axle Limits
§ 383.51: CMV alcohol-related disqualification standards
§ 391.11(b)(1): General qualifications of drivers
§ 392.22(b)(2)(v) — Divided or one-way highway placement
§ 393.70(b)(1)–(2) — Mounting and locking; Oregon Manual § 7.3.1 visual inspection
§ 395.3(a)(1)–(3) — 10-hour rest, 14-hour period, and 11-hour driving limit
§ 396.11(a)(2) — Report required when a defect or deficiency is found or reported
§ 396.11(a)(2)(i) — No-defect exception
§ 396.11(a)(2)(i)–(ii) — Report content and signature
§393.47(e)(1): Brake adjustment limits

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General Knowledge practice test

General Knowledge questions with answers

At what blood alcohol concentration does the federal CDL disqualification threshold begin for a driver operating a commercial motor vehicle that requires a CDL?

When should you downshift to control speed on a long downgrade?

What is the minimum tread depth in a major groove for a front tire on a bus, truck, or truck tractor?

The purpose of a pre-trip inspection is to:

According to the CDL manual, how often should you check your mirrors while driving?

If your commercial vehicle is hydroplaning, you should:

At speeds below 40 mph, what minimum following-distance rule applies to a commercial vehicle?

Before driving a commercial motor vehicle, what must the driver be satisfied about the cargo?

What can result from too much weight on the steering axle?

You are driving a 40-foot vehicle at 35 mph. What is the minimum following distance you should maintain?

Under the FMCSA manual's basic model, before adding air-brake lag, which three distances make up stopping distance?

If your CMV stops on the shoulder of a divided or one-way highway, where should you place warning devices?

According to federal regulations, you must inspect your cargo within the first ____ miles of your trip.

What does the federal bridge formula allow when a vehicle's axle groups are spaced farther apart?

Name two situations where you should downshift:

Retarders help slow the vehicle, but they:

What is the proper way to make a right turn in a commercial vehicle?

You are driving a 50-foot truck at 50 mph. The safe following distance is at least:

During a pre-trip, you find a vehicle condition likely to cause an accident or breakdown. What should you do?

If you have a tire failure while driving, you should:

What this test is drawn from

The other CDL knowledge tests