(a) The board shall impose a tax on all property in the district subject to district taxation.
(b) The board shall impose the tax for the benefit of the district to:
(1) pay the interest on and create a sinking fund for bonds and other obligations issued or assumed by the district for hospital purposes as provided by this chapter;
(2) pay indebtedness incurred or assumed by the district;
(3) provide for the operation and maintenance of the district and hospital system; and
(4) make improvements and additions to the hospital system.