Each resolution or ordinance providing for the appropriation of money; or establishing new positions in the classified or unclassified service of the City; or for the annual tax levy; or for improvements petitioned for by the owners of a majority of the adjacent property to be benefitted and specially assessed therefor, and any emergency ordinance necessary for the immediate preservation of public peace, health, welfare, or safety, shall take effect, unless a later date be specified therein, upon its approval by the Mayor, or upon its passage after veto by the Mayor, as the case may be.
No other resolution or ordinance shall become effective until thirty days after (1) its approval by the Mayor, or (2) the expiration of the time within which it may be vetoed by the Mayor, or (3) its passage after veto by the Mayor, as the case may be.