In carrying out any of its functions, the Commission shall have the powers authorized by the law under which such function is exercised to hold hearings, sign and issue subpenas, administer oaths, examine witnesses, and receive evidence at any place in the United States it may designate. The Commission may, by one or more of its members or by such agents as it may designate, conduct any hearing or other inquiry necessary or appropriate to its functions, except that nothing in this subsection shall be deemed to supersede the provisions of section
556 of title
5 relating to hearing examiners.