While still in college I got a Public Passenger Chauffeur's license in Indiana. I was driving school buses and YMCA buses to help pay for school. I remember the test included things about the proper lights and safety equipment, etc. I kept that license until the 'new' CDL requirements changed the license types. I didn't have the need for a CDL, I was out of school and had a 'real' job (my Dad's words) so saw no need for the hoops you had to jump through needed for the CDL or
the higher penalties for getting a ticket.
I responded to your question hoping it would kick it back up the list to get more attention. The original links I provided had some sample tests.
These links are for a CDL, much more stringent than a Class A non-commercial, but good practice and nothing like being TOO
FREE Maryland MVA CDL Practice Test 2015 | MD
Maryland MVA Practice Tests - MVA Permit Written Test - License, CDL, & Motorcycle | DMV.org
Take a Free Maryland MVA Practice Tests