(1) A majority of the board shall constitute a quorum to do business.
(2) The board shall meet at its executive offices in the city as designated by it at regularly stated times to be determined by it. Special meetings may be called by the direction of the president or vice-president or a majority of the board. A written notice of special meetings shall be given to each member of the board by the secretary.
(3) The board shall have power to declare vacant the office of a member who is absent from three consecutive regular meetings without an excuse satisfactory to the board.