Mr TRUSS (Wide Bay—Leader of The Nationals) (14:33): My question is also to the Treasurer. Does the Treasurer agree with Dr David Gruen, Executive Director of the Macroeconomic Group of the Treasury Department—his own department—that a carbon price of $50 a tonne by 2016 is conceivable? What would be the impact on electricity prices of a carbon tax of $50 a tonne?