(a) The unit, on a majority vote, shall elect from among its membership a presiding officer and an assistant presiding officer.
(b) The presiding officer and the assistant presiding officer serve terms of one year.
(c) The assistant presiding officer serves as presiding officer in the presiding officer's absence or if a vacancy occurs in that office until a new presiding officer is elected as provided by Subsection (d).
(d) If a vacancy occurs in the office of presiding officer or assistant presiding officer before the end of the vacating officer's term, the unit shall elect a person to serve the remainder of the term.