(i) the dates during which the vice-chairman may exercise those powers
and duties; and
(ii) that the powers and duties authorized to the vice-chairman shall
not be exercised by the chairman during that designated time period.
7. In case of a vacancy in the office of chairman, the clerk of the
board of supervisors shall call a meeting of the members of the board
upon like notice as provided in subdivision one, at which a successor
shall be selected chairman who shall be a member of the board. The
person so selected shall serve as chairman of the board for the
unexpired term of the previous chairman. In the event of the failure of
the board to select such chairman within thirty days after the vacancy
shall have occurred, the county clerk shall appoint a member of the
board as chairman, who shall serve until the end of the calendar year in
which he is appointed.