<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>000120 - Disclosure - Note 7. Common Stock</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><CurrencyCode /><FootnoteIndexer /><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><MCU><KeyName /><CurrencySymbol /><contextRef><ContextID>D130101_130630</ContextID><EntitySchema>http://www.sec.gov/CIK</EntitySchema><EntityValue>0000904896</EntityValue><PeriodDisplayName /><PeriodType>duration</PeriodType><PeriodStartDate>2013-01-01T00:00:00</PeriodStartDate><PeriodEndDate>2013-06-30T00:00:00</PeriodEndDate><Segments /><Scenarios /></contextRef><UPS /><CurrencyCode /><OriginalCurrencyCode /></MCU><CurrencySymbol /><Labels><Label Key="CalendarSupplement" Id="0" Label="6 Months Ended" /><Label Key="Calendar" Id="1" Label="Jun. 30, 2013" /></Labels></Column></Columns><Rows><Row FlagID="0"><Id>1</Id><IsAbstractGroupTitle>true</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>1</Level><ElementName>us-gaap_DisclosureTextBlockAbstract</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText /><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>xbrli:stringItemType</ElementDataType><SimpleDataType>string</SimpleDataType><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Notes</Label></Row><Row FlagID="0"><Id>2</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>2</Level><ElementName>us-gaap_StockholdersEquityNoteDisclosureTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="D130101_130630" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;!--egx--&gt;&lt;p style='margin:0in;margin-bottom:.0001pt'&gt;&lt;b&gt;Note 7.&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160; Common Stock&lt;/b&gt;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;In July 2010, the Company executed a Purchase Agreement, License and Development Agreement and Registration Rights Agreement (the &amp;#147;Agreements&amp;#148;), with VC Energy I, LLC of Las Vegas, NV, or VC Energy.&amp;#160; Concurrently, the Company sold VC Energy 200,000 shares of the Company's unregistered common stock, issued VC Energy 200,000 warrants and granted VC Energy an option to acquire another 400,000 common shares and 400,000 warrants.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;margin-left:58.5pt;text-align:justify'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;In August 2011, the Company and VC Energy signed a Termination Agreement and terminated the License and Development Agreement, a Promissory Note and an Escrow Agreement.&amp;#160; All other agreements between the Company and VC Energy remained in force, with certain exceptions.&amp;#160; In April 2012, the Company and VC Energy terminated the remaining agreements in effect.&amp;#160; As a result, the Company was no longer required to account for the future changes in the Company&amp;#146;s stock price after the second quarter of 2012, with regards to the warrants previously held by VC Energy.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;margin-left:58.5pt;text-align:justify'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;In both the VC Energy Agreements and its Amendment, the Company accounted for the warrants issued within the transaction with a provision that protects holders from declines in the stock price (&amp;#147;down-round&amp;#148; provisions) as a derivative security at fair value with future changes in fair value recorded in earnings.&amp;#160; As of June 30, 2013, the Company has recorded a liability of $-0- to reflect the fair value of the outstanding warrants and the removal of the &amp;#147;down-round&amp;#148; provision.&amp;#160; However, through the second quarter of 2012, the Company was periodically required to re-measure the fair value of the remaining warrants at the Balance Sheet date, with adjustments in the value recorded through the income statement as a gain or loss.&amp;#160; During the three months ended June 30, 2013 and 2012, the Company recorded a gain of $-0- and $7,400, respectively, on the revaluation and partial cancellation from the two issuances of the warrants to the end of the period.&amp;#160; During the six months ended June 30, 2013 and 2012, the Company recorded a gain of $-0- and $12,200, respectively, on the revaluation and partial cancellation from the two issuances of the warrants to the end of the period.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;In December 2010, the Company executed a Financial Public Relations Agreement with Strategic Asset Management, Inc., or SAMI.&amp;#160; The Company engaged SAMI as its non-exclusive financial public relations counsel for a term of three years.&amp;#160; For its services, the Company issued SAMI 150,000 shares of the Company's unregistered common stock.&amp;#160; The Company is recording a non-cash charge to earnings of approximately $305,000 ratably over a 36-month period starting in December 2010.&amp;#160; For each of the six months and three months ended June 30, 2013 and 2012, the charge to earnings was approximately $50,800 and $25,400, respectively.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify;text-indent:.5in'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify;text-autospace:none'&gt;In August 2011, the Company issued 100,000 shares of common stock and granted 100,000 stock warrants to SAMI for additional services performed in connection with the December 2010 Financial Public Relations Agreement.&amp;#160; To reflect the entire value of the stock and warrants issued, the Company is taking a non-cash charge to earnings of $285,700 through December 2013, the ending date of the agreement.&amp;#160; For each of the six months and three months ended June 30, 2013 and 2012, the charge to earnings was approximately $47,600 and $23,800, respectively.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify;text-indent:.5in;text-autospace:none'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify;text-autospace:none'&gt;In October 2012, the Company issued 300,000 shares of common stock and granted 150,000 stock warrants to SAMI to extend the period of services performed in connection with the December 2010 Financial Public Relations Agreement for an additional two years, through December 2015.&amp;#160; To reflect the entire value of the stock and warrants issued, the Company is recording a non-cash charge to earnings of $421,300 starting in 2013, over a 36 month period.&amp;#160; For the six months and three months ended June 30, 2013 the charge to earnings was approximately $91,000 and $57,000, respectively.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify;text-indent:.5in'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;In December 2010, the Company executed a Consulting Agreement, with SLD Capital Corporation, or SLD.&amp;#160; The Company engaged SLD to provide business consulting services for a term of eighteen months.&amp;#160; For its services, the Company issued SLD 110,000 shares of the Company's unregistered common stock.&amp;#160; The Company recorded a non-cash charge to earnings of approximately $334,000 ratably over an 18-month period starting in December 2010.&amp;#160; For the six months months ended June 30, 2013 and 2012, the charge to earnings was approximately $-0- and $98,900, respectively.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify;text-indent:.5in'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;In November 2011, the Company executed a Consulting Agreement with Rakgear, Inc.&amp;#160; The Company engaged Rakgear to provide business consulting services for a term of one year.&amp;#160; For its services, the Company issued Rakgear 50,000 shares of the Company's unregistered common stock.&amp;#160; The Company recorded a non-cash charge to earnings of $73,000 ratably over a 12-month period starting in November 2011.&amp;#160; For the six months ended June 30, 2013 and 2012, the charge to earnings was approximately $-0- and $36,500, respectively.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify;text-indent:.5in'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;In February 2012, the Company issued 15,000 shares of unregistered common stock to Financial Insights, for investor relations services for a three month period.&amp;#160; The Company recorded a non-cash charge to earnings of $19,500 during the six months ended June 30, 2012 for these shares.&amp;#160; In July 2012, Financial Insights returned all of these shares of common stock to the Company as part of an agreement and the Company reversed this charge to earnings in the third quarter of 2012.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify;text-indent:.5in'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;In March 2012, the Company issued 80,000 shares of unregistered common stock to Newport Coast Securities for financial and investor relations services for a three month period.&amp;#160; To reflect the entire value of the stock issued, the Company recorded a non-cash charge to earnings ratably during the subsequent three month period.&amp;#160; For the six months and three months ended June 30, 2012, the charge to earnings was $104,000 and $69,300, respectively.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify;text-indent:.5in'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;In August 2012, the Company issued 60,000 shares of unregistered common stock to Equiti-trend Advisors LLC/JT Trading, LLC for public relations and corporate communication services.&amp;#160; To reflect the entire value of the stock issued, the Company is recording a non-cash charge to earnings of $75,000 ratably through January 2013, the ending date of the agreement.&amp;#160; For the six months and three months ended June 30, 2013, the charge to earnings was approximately $14,500 and $-0-, respectivley.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify;text-indent:.5in'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;In December 2012, the Company borrowed $25,000 from a stockholder to provide operating capital.&amp;#160; The Note Payable was for a term of three months at an interest rate of 12%.&amp;#160; In February 2013, the stockholder converted the Note Payable to 24,760 shares of common stock, priced at the fair market value of the stock at the time of conversion.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify;text-indent:.5in'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;In January 2013, the Company issued 70,000 shares of unregistered common stock to Webracadabra Internet Works, LLC, dba Oregon Resource Innovations, for financial consulting services to be performed over a six month period.&amp;#160; To reflect the entire value of the stock issued, the Company is recording a non-cash charge to earnings of $70,000 ratably through July 2013, the ending date of the agreement.&amp;#160; For the six months and three months ended June 30, 2013 the charge to earnings was approximately $67,400 and $35,000, respectively.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;In April 2013, the Company executed a Consulting Agreement with Rakgear, Inc.&amp;#160; The Company engaged Rakgear to provide financial consulting services for a term of one year.&amp;#160; For its services, the Company issued Rakgear 150,000 shares of the Company's unregistered common stock and 150,000 warrants to puchase unregistered shares of common stock at a price of $1.49 per warrant.&amp;#160; To reflect the entire value of the stock issued, the Company is recording a non-cash charge to earnings of $487,900 ratably through March 2014, the ending date of the agreement.&amp;#160; For the three months ended June 30, 2013 the charge to earnings was approximately $122,000.&lt;/p&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for shareholders' equity, comprised of portions attributable to the parent entity and noncontrolling interest, if any, including other comprehensive income (as applicable).  Including, but not limited to: (1) balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings; (2) accumulated balance for each classification of other comprehensive income and total amount of comprehensive income; (3) amount and nature of changes in separate accounts, including the number of shares authorized and outstanding, number of shares issued upon exercise and conversion, and for other comprehensive income, the adjustments for reclassifications to net income; (4) rights and privileges of each class of stock authorized; (5) basis of treasury stock, if other than cost, and amounts paid and accounting treatment for treasury stock purchased significantly in excess of market; (6) dividends paid or payable per share and in the aggregate for each class of stock for each period presented; (7) dividend restrictions and accumulated preferred dividends in arrears (in aggregate and per share amount); (8) retained earnings appropriations or restrictions, such as dividend restrictions; (9) impact of change in accounting principle, initial adoption of new accounting principle and correction of an error in previously issued financial statements; (10) shares held in trust for Employee Stock Ownership Plan (ESOP); (11) deferred compensation related to issuance of capital stock; (12) note received for issuance of stock; (13) unamortized discount on shares; (14) description, terms, and number of warrants or rights outstanding; (15) shares under subscription and subscription receivables, effective date of new retained earnings after quasi-reorganization and deficit eliminated by quasi-reorganization and, for a period of at least ten years after the effective date, the point in time from which the new retained dates; and (16) retroactive effective of subsequent change in capital structure.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Regulation S-X (SX)

 -Number 210

 -Section 08

 -Article 4



Reference 2: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 30

 -Section 50

 -Paragraph 2

 -URI http://asc.fasb.org/extlink&amp;oid=6405834&amp;loc=d3e23285-112656



Reference 3: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Regulation S-X (SX)

 -Number 210

 -Section 02

 -Paragraph 29, 30, 31

 -Article 5



Reference 4: http://www.xbrl.org/2003/role/presentationRef

 -Publisher AICPA

 -Name Accounting Research Bulletin (ARB)

 -Number 43

 -Section B

 -Paragraph 7, 11A

 -Chapter 1

 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 5: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 6

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21506-112644



Reference 6: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Statement of Financial Accounting Standard (FAS)

 -Number 5

 -Paragraph 15

 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 7: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 310

 -SubTopic 10

 -Section S99

 -Paragraph 2

 -Subparagraph (SAB TOPIC 4.E)

 -URI http://asc.fasb.org/extlink&amp;oid=6228006&amp;loc=d3e74512-122707



Reference 8: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Glossary Preferred Stock

 -URI http://asc.fasb.org/extlink&amp;oid=6521494



Reference 9: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section S99

 -Paragraph 4

 -Subparagraph (SAB TOPIC 4.C)

 -URI http://asc.fasb.org/extlink&amp;oid=6959260&amp;loc=d3e187143-122770



Reference 10: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 235

 -SubTopic 10

 -Section S99

 -Paragraph 1

 -Subparagraph (SX 210.4-08.(d),(e))

 -URI http://asc.fasb.org/extlink&amp;oid=6881521&amp;loc=d3e23780-122690



Reference 11: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Statement of Financial Accounting Standard (FAS)

 -Number 129

 -Paragraph 2, 3, 4, 5, 6, 7, 8

 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 12: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Staff Accounting Bulletin (SAB)

 -Number Topic 4

 -Section C



Reference 13: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Staff Accounting Bulletin (SAB)

 -Number Topic 4

 -Section E



Reference 14: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 210

 -SubTopic 10

 -Section S99

 -Paragraph 1

 -Subparagraph (SX 210.5-02.29-31)

 -URI http://asc.fasb.org/extlink&amp;oid=6877327&amp;loc=d3e13212-122682



Reference 15: http://www.xbrl.org/2003/role/presentationRef

 -Publisher AICPA

 -Name Accounting Principles Board Opinion (APB)

 -Number 12

 -Paragraph 10

 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 16: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Regulation S-X (SX)

 -Number 210

 -Section 04

 -Article 3



Reference 17: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 2

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21463-112644



Reference 18: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section S99

 -Paragraph 1

 -Subparagraph (SX 210.3-04)

 -URI http://asc.fasb.org/extlink&amp;oid=6959260&amp;loc=d3e187085-122770



Reference 19: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 11

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21564-112644



Reference 20: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 3

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21475-112644



Reference 21: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 4

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21484-112644



Reference 22: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 5

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21488-112644



Reference 23: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Regulation S-X (SX)

 -Number 210

 -Section 08

 -Paragraph d

 -Article 4



</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Note 7. Common Stock</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>Note 7. Common Stock</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>true</HasCustomUnits><IsEmbedReport>false</IsEmbedReport><IsMultiCurrency>false</IsMultiCurrency><ReportType>Sheet</ReportType><RoleURI>http://www.nviro.com/20130630/role/idr_DisclosureNote7CommonStock</RoleURI><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows></InstanceReport>
