§ 100. Mandatory referendum. When a resolution of the board of
supervisors is subject to a mandatory referendum, such board shall by
resolution cause such resolution to be submitted to a vote of the
qualified electors of the county for their approval or disapproval at a
general or special election. Except as otherwise provided by law, the
resolution shall fix a date not less than forty-five days after its
adoption on which the proposition is to be submitted at such general or
special election.