(a) An authority shall reimburse a board member for all necessary expenses incurred in the discharge of official authority duties.
(b) Except as provided by Subsection (c), an authority in which the principal municipality has a population of more than 1.1 million shall pay a member $50 for each meeting of the board attended by the member not exceeding five meetings in a calendar month.
(c) A board member in an authority created by an alternate municipality receives no compensation for attending a board meeting.