(a) On final approval of the budget, the board shall impose a tax on all property in the district subject to district taxation.
(b) The tax may be used to:
(1) pay the indebtedness assumed or issued by the district;
(2) provide for the maintenance and operation of the district and hospital system;
(3) make improvements and additions to the hospital system; and
(4) acquire necessary sites for the hospital system by purchase, lease, or condemnation.
(c) The district may not impose a tax to pay the principal of or interest on revenue bonds issued by the district.