(b) By any taxing district otherwise authorized by law to issue general obligation bonds for capital purposes, for the sole purpose of making the required payments of principal and interest on general obligation bonds issued solely for capital purposes, other than the replacement of equipment, when authorized so to do by majority of at least three-fifths of the electors thereof voting on the proposition to issue such bonds and to pay the principal and interest thereon by an annual tax levy in excess of the limitation herein provided during the term of such bonds, submitted not oftener than twice in any calendar year, at an election held in the manner provided by law for bond elections in such taxing district, at which election the total number of persons voting on the proposition shall constitute not less than forty per centum of the total number of votes cast in such taxing district at the last preceding general election: Provided, That any such taxing district shall have the right by vote of its governing body to refund any general obligation bonds of said district issued for capital purposes only, and to provide for the interest thereon and amortization thereof by annual levies in excess of the tax limitation provided for herein, and Provided further, That the provisions of this section shall also be subject to the limitations contained in Article VIII, Section 6, of this Constitution;
(c) By the state or any taxing district for the purpose of paying the principal or interest on general obligation bonds outstanding on December 6, 1934; or for the purpose of preventing the impairment of the obligation of a contract when ordered so to do by a court of last resort.
