(a) Every person holding a license issued by a division of the board shall display it in a conspicuous manner at his place of business.
(b) All commercial vehicles used by licensees and certificate holders exclusively in the daily operation of their business shall have prominently displayed thereon the company or business registration number issued by the Secretary of State’s office. Such registration number shall also be prominently displayed on any advertising in telephone yellow pages and newspapers relating to work which a licensee or certificate holder purports to have the capacity to perform. Said registration number shall also be printed on all invoices and proposal forms.