(a) A state agency shall print a telephone number for the agency on the letterhead of its official stationery.
(b) In this section, "state agency" means:
(1) a board, commission, department, office, or other agency in the executive branch of state government that was created by the constitution or a statute of the state, including an institution of higher education as defined by Section 61.003, Education Code;
(2) the legislature or a legislative agency;
(3) the supreme court, the court of criminal appeals, a court of appeals, or a state judicial agency; or
(4) a river authority.