The form of ballot in the election for the adoption or rejection of the proposed charter shall be: "For the proposed charter," "Against the proposed charter." In submitting the proposed charter or amendments thereto, any alternate article or proposition may be presented for the choice of the voters and may be voted on separately without prejudice to others. In submitting such amendment, article or proposition, the form of the ballot shall be: "For article No. . . . . of the charter," "Against article No. . . . . of the charter."