FILE - This Wednesday, Sept. 21, 2016, file photo shows Exxon Mobil's Billings Refinery in Billings, Mont. President-elect Donald Trump this week tapped ExxonMobil CEO Rex Tillerson to serve as his secretary of state. If confirmed by the Senate, where opposition is emerging, the move could have broad consequences for U.S. environmental policy and affect the role the U.S. plays in multinational discussions about climate change.
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