A taxable item sold, leased, or rented to, or stored, used, or consumed by, any of the following governmental entities is exempted from the taxes imposed by this chapter:
(2) an unincorporated instrumentality of the United States;(3) a corporation that is an agency or instrumentality of the United States and is wholly owned by the United States or by another corporation wholly owned by the United States;(5) a county, city, special district, or other political subdivision of this state; or(6) a state, or a governmental unit of a state that borders this state, but only to the extent that the other state or governmental unit exempts or does not impose a tax on similar sales of items to this state or a political subdivision of this state. Amended by Acts 1993, 73rd Leg., ch. 719, Sec. 1, eff. July 1, 1993 Acts 1981, 67th Leg., p. 1560, ch. 389, Sec. 1, eff. Jan. 1, 1982.