All revenue in excess of all obligations of the authority of any nature, together with all unused receipts and gifts of every kind and nature whatsoever, shall be and become the authority fund. The authority, in its discretion, is charged with the duty of pledging, utilizing, or expending the authority fund for the following purposes:

(1) Pledges to the payment of any revenue bond issue requirements, sinking or reserve funds, as may be provided for under Code Section 32-10-102;

(2) The payment of any outstanding unpaid revenue bond obligations or administrative expenses;

(3) The construction of all or any part of projects, the need for which is concurred in by the Governor and the board;

(4) The most advantageous obtainable redemptions and retirements of the authority's bonds pursuant to the prepayment redemption privileges accorded to the authority upon the various issues of bonds outstanding;

(5) The most advantageous open market purchase of the authority's bonds that the authority may accomplish;

(6) Investment in such securities and in such manner as it determines to be in its best interest; and

(7) Subject to the terms of any resolution or trust indenture authorizing the issuance of revenue bonds, the transfer of funds to the department to be used by the department for department purposes.