(a) District bonds and notes are legal and authorized investments for:
(1) a bank;
(2) a trust company;
(3) a savings and loan association; and
(4) an insurance company.
(b) The bonds and notes are:
(1) eligible to secure the deposit of public funds of this state or a municipality, a county, a school district, or any other political corporation or subdivision of this state; and
(2) lawful and sufficient security for the deposit to the extent of the principal amount or market value of the bonds or notes, whichever is less.