Sec. 17. POWERS OF BOARD.  The Board shall adopt proper forms and regulations, rules and contracts as will in its best judgment protect the income from lands leased hereunder.  A majority of the Board shall have power to act in all cases, except where otherwise herein provided.  The Board may reject any and all bids and shall have the further right to withdraw any lands advertised for lease prior to receiving and opening bids.  Any and all or parts of laws in conflict with this Act are hereby repealed.