Question What is the minimum permitted size of a placard? Answers Four square inches Seven square inches 10 ¾ square inches 32 square inches Explanation Hazardous materials must be diamond-shaped and a size of at least 10 ¾ square inches. This questions appears in the following tests: District Of Columbia Passenger Indiana Class A Knowledge Test Indiana Double Massachusetts Class A Knowledge Test Massachusetts Passenger New Jersey Double North Dakota Class A Knowledge Test West Virginia Class B Knowledge Test West Virginia Passenger