what are the estimations of expenditure regarding this?
Costs estimates were found to be much lower than those estimated in the previous IPCC Third Assessment Report; 0.05% of Annex B GDP
Kyoto Protocol
Due to US non-participation in the Kyoto treaty, costs estimates were found to be much lower than those estimated in the previous IPCC Third Assessment Report. Without the US participation, and with full use of the Kyoto flexible mechanisms, costs were estimated at less than 0.05% of Annex B GDP. 
what was a major contributor to the collapse of enron in 2001 Enron scandal who were associated with this scandal? Jeffrey Skilling and his staff of executives, Andrew Fastow and Arthur Andersen were any steps taken against them? Enron shareholders filed a $40 billion lawsuit after the company's stock price plummeted to less than $1 by the end of November 2001 was the government criticized for this as well? Yes, critics of Bush and his administration attempted to link them to the scandal what is the full name of the aforementioned person? George W. Bush who was he? American politician and businessman who served as the 43rd president of the United States what policies did he adopt regarding environment? He opposed the Kyoto Protocol, signed an executive order to create an interagency task force to streamline energy projects, and announced the Clear Skies Act of 2003 what was this protocol about? It is an international treaty which extends the 1992 UNFCCC, that commits state parties to reduce greenhouse gas emissions is there any such nation which was once a part of it but later withdrew? Yes, Canada
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Kyoto Protocol [SEP] Cost estimates
Barker "et al." (2007, p. 79) assessed the literature on cost estimates for the Kyoto Protocol. Due to US non-participation in the Kyoto treaty, costs estimates were found to be much lower than those estimated in the previous IPCC Third Assessment Report. Without the US participation, and with full use of the Kyoto flexible mechanisms, costs were estimated at less than 0.05% of Annex B GDP. This compared to earlier estimates of 0.1–1.1%. Without use of the flexible mechanisms, costs without the US participation were estimated at less than 0.1%. This compared to earlier estimates of 0.2–2%. These cost estimates were viewed as being based on much evidence and high agreement in the literature.