All classes of CDL require a DOT medical card - A, B, and C. Additionally, anyone operating a commercial vehicle with a GVWR in excess of 10,000 lbs. is required to have one, even if the vehicle doesn't require a CDL.
To operate ANY vehicle which requires a CDL of ANY class in ALL states (this is federal law - it doesn't vary by state), the driver must have, along with the appropriate class of CDL (A, B, C), a DOT Medical Card. However, this is assuming you're were referring to a Class C CDL - several states issue a non-CDL Class C licence.
Not sure what you mean, exactly. Class A is considered the "higher" classification, yes. If you have a Class A CDL, you can operate vehicles requiring that class of licence or any class below that. You could operate a vehicle requiring a Class B CDL, for example, but a driver with a Class B CDL wouldn't be permitted to operate a combination requiring a Class A CDL.
For Class 7 and Class 8 trucks which are registered farm use vehicles, most states require the operator have a current DOT medical card.
CDL classes are A, B, and C - there is no Class D CDL.
Depends on which Class of CDL. A driver with a Class C CDL is not licensed on that vehicle. A driver with a Class B CDL can drive that combination only if the GVW of the trailer is less than 10,000 lbs. A driver with a Class A CDL can drive it.
Not only any public roadway. This vehicle requires an active CDL, and if your DOT physical is expired, your CDL is null and void.
Yes.
Class 3 truck with a rollback body? No, it doesn't require a CDL.
If you have a CDL, you're required to have a current and valid medical card, period.
You can obtain a CDL class B license at your local DMV. To obtain a CDL class B license you are required to take several tests before obtaining your license.
You will need a Class B CDL with tanker endorsement.
Depends. You can drive up to a Class 6 truck (up to 26,000 lbs. GVWR) without a CDL. Class 7 or Class 8 trucks require a CDL.