The municipal government provided for by this Charter shall be known as "council- manager form of government." All powers of the City shall be exercised in the manner prescribed by this Charter or, if the manner be not prescribed, then in such manner as the council may prescribe by ordinance and if not addressed either in the Charter or by city ordinance, then in such manner as prescribed by state law. The words "council" and "commission" may be used interchangeably and shall have the same meaning and reference.