The following must be presumed unless a party to the proceeding, by reasonable notice, requires proof of it—
(a) the chief executive’s appointment;
(b) a chief executive officer’s appointment;
(c) an authorised person’s appointment;
(d) a contact tracing officer’s appointment;
(e) an emergency officer’s appointment;
(f) a designated medical officer’s appointment;
(g) a state analyst’s appointment;
(h) the authority of the chief executive, a local government, a chief executive officer, an authorised person, a contact tracing officer, an emergency officer, a designated medical officer or a state analyst, to do anything under this Act.