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For years governments around the world have attempted to come to agreements to reduce carbon dioxide emissions. Success has been limited for a variety of reasons. Select the item from the list provided to make the following statements true. To reduce the emission of carbon governments could aim to 1. Negative externality low carbon electricity generation technologies, 2. Positive externality such as wind farms. 3. Tax 4. Subsidise The high cost of negotiation may make it to 5. Command and control come to an agreement to reduce carbon emissions. 6. Negotiate Assuming current theories on global warming to be true, the 7. Possible current levels of carbon emissions are 8. Impossible 9. Private 10. Efficient 11. Inefficient 12. Social