(a) The Commission may order any person, sole proprietorship, partnership, or corporation being investigated to answer written interrogatories. Such interrogatories shall be answered by the individual or by any agent or officer of the sole proprietorship, partnership, or corporation who shall furnish information on behalf of the sole proprietorship, partnership, or corporation. The information provided shall be that which is known or reasonably available to the person or organization involved and shall be submitted after reasonable inquiry to obtain the information requested.

(b) Each interrogatory shall be answered separately and fully in writing, under oath, unless it is objected to, in which event the reason for the objection shall be stated in lieu of an answer. The answers shall be signed by the individual or the officer or agent making them. The person, sole proprietorship, parnership, or corporation upon whom the interrogatories have been served shall furnish the Commission a copy of the answers and objections, if any, within 30 days after service of the interrogatories or within such shorter time as the commission may designate. Interrogatories submitted hereunder are continuing in character so as to require the person, sole proprietorship, partnership, or corporation answering to file supplementary answers upon obtaining further or different information.