; and (2) receive travel expenses, including per diem in lieu of subsistence, in accordance with applicable provisions under subchapter I of chapter 57 of title 5, United States Code. 309. Authorization of appropriations There are authorized to be appropriated to the Director to carry out this Act $550,000,000 for each of the fiscal years 2024, 2025, 2026, 2027, and 2028. IV Enforcement 401. Investigations and administrative discovery (a) Joint investigations The Agency or, where appropriate, an Agency investigator, may conduct investigations and make requests for information, as authorized under this Act, on a joint basis with another Federal agency, a State attorney general, or a State privacy regulator. (b) Subpoenas (1) In general The Agency or an Agency investigator may issue subpoenas for the attendance and testimony of witnesses and the production of relevant papers, books, documents, or other material in connection with hearings under this Act. (2) Failure to obey In the case of contumacy or refusal to obey a subpoena issued pursuant to this subsection and served upon any person, the district court of the United States for any district in which such person is found, resides, or transacts business, upon application by the Agency or an Agency investigator and after notice to such person, may issue an order requiring such person to appear and give testimony or to appear and produce documents or other material. (3) Contempt Any failure to obey an order of the court under paragraph (2) may be punished by the court as a contempt thereof. (c) Demands (1) In general Whenever the Agency has reason to believe that any person may be in possession, custody, or control of any documentary material or tangible things, or may have any information, relevant to a violation, the Agency may, before the institution of any proceedings under this Act, issue in writing, and cause to be served upon such person, a civil investigative demand requiring such person to— (A) produce such documentary material for inspection and copying