(a) The powers of each authority are vested in the commissioners.
(b) A quorum is:
(1) three commissioners of a five-member authority;
(2) four commissioners of a seven-member authority; or
(3) five commissioners of a nine-member authority.
(c) An authority may take action on a vote of a majority of the commissioners present at a meeting at which there is a quorum, unless a larger number is required by law or the bylaws of the authority.