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USD ($)

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   &lt;div style="margin-top: 12pt; font-size: 1pt"&gt;&amp;#160;
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       &lt;b&gt;&lt;font style="font-family: Arial, Helvetica"&gt;Basis of
       consolidation&lt;/font&gt;&lt;/b&gt;
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       All majority-owned subsidiaries in which we have both share and
       management control are consolidated. All significant
       intercompany accounts and transactions are eliminated.
       Subsidiaries over which control is achieved through other means,
       such as stockholders agreement, are also consolidated even if we
       hold less than 51% of voting capital. Our variable interest
       entities in which we are the primary beneficiary are
       consolidated. Investments in unconsolidated affiliates and joint
       ventures are accounted for under the equity method
       (Note&amp;#160;15).
   &lt;/div&gt;
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   &lt;div align="left" style="margin-left: 3%; margin-right: 0%; text-indent: 0%; font-size: 10pt; font-family: Arial, Helvetica; color: #000000; background: transparent"&gt;
       We evaluate the carrying value of our equity investments in
       relation to publicly quoted market prices when available. If the
       quoted market price is below book value, and such decline is
       considered other than temporary, we write-down our equity
       investments to quoted market value.
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       We define joint ventures as businesses in which we and a small
       group of other partners each participate actively in the overall
       entity management, based on a stockholders agreement. We define
       affiliates as businesses in which we participate as a
       noncontrolling interest but with significant influence over the
       operating and financial policies of the investee.
   &lt;/div&gt;
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       Our participation in hydroelectric projects in Brazil is made
       via consortium contracts under which we have undivided interests
       in the assets, and are liable for our proportionate share of
       liabilities and expenses, which are based on our proportionate
       share of power output. We do not have joint liability for any
       obligations. No separate legal or tax status is granted to
       consortia under Brazilian law. Accordingly, we recognize our
       proportionate share of costs and our undivided interest in
       assets relating to hydroelectric projects (Note&amp;#160;12).
   &lt;/div&gt;
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 -Publisher FASB
 -Name FASB Staff Position (FSP)
 -Number FAS140-4 and FIN46(R)-8
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher AICPA
 -Name Accounting Research Bulletin (ARB)
 -Number 51
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher AICPA
 -Name Statement of Position (SOP)
 -Number 94-6
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name FASB Interpretation (FIN)
 -Number 46R
 -Paragraph 4, 14, 15

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