Senator BOB BROWN (Tasmania—Leader of the Australian Greens) (14:36): My question goes to— Honourable senators interjecting— The PRESIDENT: Order! Senator Brown, resume your seat. As long as those exchanges across the chamber are taking place, it makes it difficult for me to hear your question. That is not fair to you. You are entitled to be heard in silence. Senator BOB BROWN: It is not fair to you either, Mr President. My question is to the Minister representing the Treasurer, Senator Wong. I refer to the full-page ad in today's Sydney Morning Herald and other entities by the Australian Coal Association, which might more readily be called the Overseas Owned Coal Association. I ask the minister: is such advertising tax deductible? If so, does the government know how many thousands of dollars of this advertising is coming out of taxpayers' pockets without their warrant?