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       &lt;td&gt;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,
   one 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 11).&lt;/td&gt;
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       &lt;td&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.&lt;/td&gt;
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       &lt;td&gt;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;/td&gt;
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       &lt;td&gt;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.&lt;/td&gt;
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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