E. The board shall appoint the chief executive officer of the authority, who shall not be a member thereof, to be known as the director of that authority, hereinafter referred to as director, and whose compensation shall be paid by the authority in the amount determined by the board. The board shall employ or retain such other agents or employees subordinate to the director as may be necessary, including persons with special qualifications, and shall determine which such agents or employees shall be bonded and the amount of such bonds. The director and other agents and employees so appointed shall serve at the pleasure of the board, which shall fix their compensation and prescribe their duties. The board shall elect from its membership a chairman, vice-chairman, a secretary and a treasurer, or secretary-treasurer, and shall prescribe their powers and duties. Four members shall constitute a quorum of the board for the purpose of conducting its business and exercising its powers and for all other purposes. The board shall keep detailed minutes of its proceedings, which shall be open to public inspection. It shall keep suitable records of all of its financial transactions and shall arrange to have the same audited annually.