The Director of the Department of Small Business and Supplier Diversity shall appoint the Executive Director of the Authority. The Executive Director shall administer, manage and direct the affairs and activities of the Authority in accordance with the policies and under the control and the direction of the Board and the Director of the Department of Small Business and Supplier Diversity. Except as otherwise stated in this article, the Executive Director shall approve all accounts for allowable expenses for the Authority or of any employee or consultant or other person providing services to the Board, and for expenses incidental to the operation of the Authority subject to approval of the Director of the Department of Small Business and Supplier Diversity. The Executive Director shall maintain and be custodian of all books, documents and papers of or filed with the Authority, including but not limited to the minute book or journal of the Authority, and of its official seal. The Executive Director may cause copies to be made of all minutes and other records and documents of the Authority and may in the place and stead of the Secretary of the Authority give certificates under seal of the Authority to the effect that such copies are true copies, and all persons dealing with the Authority may rely on such certificates. The Executive Director also shall perform such other duties as prescribed by the Board in carrying out the purposes of this article.