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                   with a copy (which shall not constitute notice) to:

                   Gresham, Davis, Gregory, Worth & Moore
                   A Professional Corporation
                   112 East Pecan Street
                   Suite 900
                   San Antonio, Texas 78205-1204
                   Facsimile Number: 210/226-5154
                   Attention: Marshall B. Miller, Jr.

               If to Zapata Corporation then to:

                   Zapata Corporation
                   One Riverway, Suite 2200
                   777 South Post Oak Lane
                   Houston, Texas 77056
                   Facsimile Number: 713/940-6111
                   Attention: Corporate Secretary

                   with a copy (which shall not
                   constitute notice) to:

                   Baker & Botts, L.L.P.
                   3000 One Shell Plaza
                   Houston, Texas 77002
                   Facsimile Number: 713/229-1522
                   Attention: Roy L Nolen

     or to such other address as the addressee may have specified in a notice
     duly given to the sender as provided herein. Such notice, request, demand,
     waiver, consent, approval or other communication will be deemed to have
     been given as of the date so delivered or electronically transmitted or
     sent after mailing thereof.

           10. This Agreement represents the entire understanding of the parties
     hereto relating to the subject matter hereof, supersedes any prior
     agreements between the parties and the terms and provisions of this
     Agreement may not be modified or amended, except in writing. Any failure or
     delay on the part of either party in exercising any power or right
     hereunder shall not operate as a waiver thereof, nor shall any single or
     partial exercise of any such right or power preclude any other or further
     exercise thereof or the exercise of any other right or power hereunder.

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