The board shall annually elect a chairperson and vice-chairperson from its members and a secretary and treasurer who shall not be a member of the board. A quorum for the transaction of business shall consist of four members of the board. The affirmative vote of four members shall be necessary for any action taken by the board. No vacancy in the membership shall impair the right of the quorum to exercise all the rights and perform all the duties of the board. The members of the board shall receive no compensation for services rendered, but shall be reimbursed for all expenses incurred by them in the exercise of their duties in the same manner as provided in section 23-1112 for county officers and employees and for the cost of their bonds. The secretary and treasurer may be compensated in such amounts as the board shall fix from time to time, and such persons may be required to give bond, in the amount prescribed by the board, before entering upon the duties of secretary or treasurer. The premium of such bond shall be paid for by the board.