In addition to any regulation specifically required by this subtitle, regulations that the Commissioner adopts to carry out this subtitle may include: definitions of the terms “administrative capacity”, “executive capacity”, “professional capacity”, and “outside salesman”; a scale of wages that is suitable for learners and apprentices but is at least 80% of the minimum wage under this subtitle; and a wage for a special case or class of case if the Commissioner finds the wage appropriate to: avoid undue hardship; prevent the curtailment of employment opportunity; and safeguard the minimum wage under this subtitle.