Where the 419 feet at 55 mph goes and which part of it obeys the square law, downgrades and brake fade, how much space to keep in six directions and why a long vehicle turns wide only at the end, seeing and signalling and the limits of your own headlights, traction and the two kinds of skid, reading hazards early, and what to do when there is no room left to stop.
Score 80% or higher to earn a certificate.
Numbers are the CDL manual’s own where the manual gives one. Where it gives a rule of thumb rather than a figure, the explanation says which it is.