The tax administrator may prescribe rules and regulations, not inconsistent with law, to carry into effect the provisions of this chapter. These rules and regulations, when reasonably designed to carry out the intent and purpose of this chapter, are prima facie evidence of its proper interpretation. These rules and regulations may from time to time be amended, suspended, or revoked, in whole or in part, by the tax administrator. The tax administrator may prescribe and furnish any forms necessary or proper for the administration of this chapter.