All determinations made by the Authority in the exercise of its discretionary powers, with the approval of the Governor if such approval is expressly required by the provisions of this Act, including without limitation, the location and terminal points of any toll highway or section to be constructed by it, the materials to be used in its construction, the plans and specifications thereof, the tolls to be charged for the use thereof, and the letting of contracts for the construction of toll highways or any part thereof, or the sale of bonds, shall be conclusive and shall not be subject to review by the courts or by any administrative agency of the State.