(a) The board shall impose on all property subject to district taxation, for the benefit of the district, a tax at a rate not to exceed 75 cents on each $100 assessed value of the property according to the most recent certified appraisal roll of the district.
(b) The board shall impose the tax to:
(1) meet the requirements of the district's bonds;
(2) provide for the district's maintenance and operating expenses;
(3) make improvements and additions to the district's hospitals or hospital system; and
(4) acquire necessary sites for hospitals or the hospital system by gift, purchase, lease, or condemnation.