Subject to the approval of the governor and council, the commissioner of health and human services shall appoint a deputy commissioner who shall serve for a term of 4 years. The deputy commissioner shall perform such duties as may be assigned by the commissioner, which may include, but not be limited to, the authority and power with approval of the commissioner to direct and supervise the operation and administration of any division of the department. The annual salary of the deputy commissioner shall be as prescribed in N.H. Rev. Stat. § 94:1-a.