(1) Any retailer who, in contravention of the policy of this part, advertises, offers to sell, or sells at retail any merchandise at less than cost to the retailer, as defined in this part, commits a Class C misdemeanor.
(2) Any wholesaler who, in contravention of the policy of this part, advertises, offers to sell, or sells at wholesale any merchandise at less than cost to the wholesaler, as defined in this part, commits a Class C misdemeanor.
(3) Proof of any such advertising, offer to sell, or sale by any retailer or wholesaler in contravention of the policy of this part shall be prima facie evidence of a violation of this part.