What are the full relevant details of the (a) purchase of a farm belonging to Fortuinskolk of the Rossouw Olivier Familietrust in Carnarvon that was sold to the Government, (b) comparative market values and prices of the farms that were sold in the Carnavon area between 2014 and 2023, (c) indicators that the farm was bought within the realistic market value and (d) reasons for staying within the market values?