Question If required, ____ identical placards must be placed on a vehicle. Answers Two Four Six Eight Explanation When hazardous materials placards are required, a vehicle must display four identical placards. A placard should be placed on the front, on the rear, and on both sides of the vehicle. This questions appears in the following tests: District Of Columbia HazMat Indiana HazMat Maryland HazMat Massachusetts HazMat New Jersey HazMat Utah Tank West Virginia HazMat