(a) The board shall impose a tax on all taxable property in the district subject to district taxation.
(b) The board shall impose the tax to:
(1) pay the interest on and create a sinking fund for bonds or other obligations issued by the district for hospital purposes as provided by this chapter;
(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.