Document:

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                                                                    EXHIBIT 10-C
                                                                    ------------

                                                     ACE JOINTLY OWNED AGREEMENT

                               SECOND AMENDMENT
                                    TO THE
                          PURCHASE AND SALE AGREEMENT
                                BY AND BETWEEN
                        ATLANTIC CITY ELECTRIC COMPANY
                                      AND
                               NRG ENERGY, INC.

          SECOND AMENDMENT TO THE PURCHASE AND SALE AGREEMENT (the "Second
Amendment") by and between Atlantic City Electric Company, a New Jersey
corporation ("ACE" or "Seller"), and NRG Energy, Inc., a Delaware corporation
("Buyer"), dated as of October 31, 2001.  Seller and Buyer may each be referred
to herein individually as a "Party" and collectively as the "Parties."
Capitalized terms used and not otherwise defined in this Second Amendment shall
have the respective meanings assigned to them in the Amended Agreement (as
defined below).

          WHEREAS, Seller and Buyer are Parties to the Purchase and Sale
Agreement, dated as of January 18, 2000 (the "Agreement"), and the Amendment to
the Agreement, dated as of June 22, 2001 (the "First Amendment" and, together
with the Agreement, the "Amended Agreement"), providing for the sale and
assignment by Seller of the Purchased Assets and the Assumed Liabilities and the
purchase and assumption by Buyer of the Purchased Assets and the Assumed
Liabilities, upon the terms and conditions set forth in the Amended Agreement;
and

          WHEREAS, the Closing of the transactions contemplated by the Amended
Agreement and the ACE Related Purchase Agreement, as amended, has been
unexpectedly delayed; and

          WHEREAS, as a result of the delay of the Closing, the Parties desire
to further amend the Amended Agreement as set forth herein and the ACE Related
Purchase Agreement, as amended, as set forth in the amendment thereto, which is
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being entered into simultaneously with this Second Amendment, to, among other
things, extend the termination date of the Amended Agreement and the ACE Related
Purchase Agreement, as amended.

          NOW THEREFORE, for good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, Seller and Buyer hereby agree as
follows:

                                   ARTICLE 1

           Amendment of Certain Provisions of the Amended Agreement
           --------------------------------------------------------

          Section 1.1   Certain Representations and Warranties of Seller
                        ------------------------------------------------
Section 4.2 of the Agreement is hereby amended and restated in its entirety to
read as follows:

               "Seller has full corporate power and authority to execute and
     deliver this Agreement and each Additional Agreement to which it is a party
     and to consummate the transactions contemplated hereby and thereby.  Except
     for the approval of the proviso to clauses (iii) of Section 9.1(b) hereof
     by the Board of Directors of Seller, the execution and delivery by Seller
     of this Agreement and each Additional Agreement to which it is a party and
     the consummation by Seller of the transactions contemplated hereby and
     thereby have been duly and validly authorized by all necessary corporate
     action required on the part of Seller.  This Agreement has been duly and
     validly executed and delivered by Seller and, subject to the receipt of
     Seller's Required Regulatory Approvals, this Agreement constitutes, and
     upon the execution and delivery by Seller of each Additional Agreement to
     which it is a party, each such Additional Agreement will constitute, the
     legal, valid and binding obligation of Seller, enforceable against Seller
     in accordance with its terms, except that such enforceability may be
     limited by applicable bankruptcy, insolvency, reorganization, fraudulent
     conveyance, moratorium or other similar Laws affecting or relating to
     enforcement of creditors' rights generally and general principles of equity
     (regardless of whether enforcement is considered in a proceeding at law or
     in equity)."

                                       2
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          Section 1.2  Certain Covenants of the Parties.  Section 6.4 of the
                       --------------------------------
Agreement is hereby amended to include the following additional provisions:

               "(e)  Without limiting the generality of Section 6.4(b) of the
     Agreement, from and after the date of this Second Amendment, Seller and
     Buyer shall reasonably cooperate with each other to supplement the
     testimony provided to the NJBPU prior to the date hereof."

          Section 1.3  Certain Termination Provisions.  Section 9.1(b) of the
                       ------------------------------
Agreement, as amended by Section 1.3 of the First Amendment, is hereby amended
and restated in its entirety to read as follows:

               "This Agreement may be terminated by Seller, on the one hand, or
     Buyer, on the other hand, upon written notice to the other Party, (i) at
     any time prior to the Closing if any court of competent jurisdiction shall
     have issued an order, judgment or decree permanently restraining, enjoining
     or otherwise prohibiting the Closing, and such order, judgment or decree
     shall have become final and nonappealable; (ii) at any time prior to the
     Closing if any Law shall have been enacted or issued by any Governmental
     Authority which, directly or indirectly, prohibits the consummation of the
     transactions contemplated by this Agreement or by any Additional Agreement;
     or (iii) at any time after December 31, 2001, if the Closing shall not have
     occurred on or before such date, provided, however, that neither Seller nor
     Buyer shall be permitted to so terminate this Agreement at any time prior
     to March 1, 2002, if the Board of Directors of Seller shall have approved
     this proviso to this clause (iii) on or prior to December 31, 2001; and,
     provided, further, that the right to terminate this Agreement under Section
     9.1(b)(iii) shall not be available to any Party whose breach of this
     Agreement has caused, or resulted in, the failure of the Closing to occur
     on or before such applicable date."

                                  ARTICLE II

                   Release, Waiver and Additional Provisions
                   -----------------------------------------

                                       3
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          Section 2.1  Release and Waiver of Claims Against Seller Parties.
                       ---------------------------------------------------

               (a) Buyer and each of its Affiliates hereby unconditionally and
irrevocably releases, acquits and forever discharges Seller and its Affiliates,
shareholders, officers, directors, employees, agents, representatives,
successors and assigns (collectively, the "Seller Parties"), effective as of the
                                           --------------
date hereof, of and from, and hereby unconditionally and irrevocably waives, any
and all claims, demands, debts, losses, costs, expenses, proceedings, judgments,
damages, actions, causes of action, suits, contracts, agreements, obligations,
accounts and liabilities of any kind or character whatsoever, known or unknown,
suspected or unsuspected, in contract or in tort, at law or in equity
("Claims"), that the Buyer or any of its Affiliates alone or with any other
Person had, now has, or might hereafter have against the Seller Parties or any
of them jointly and/or severally, for or by reason of any matter, circumstance,
event, action, omission, cause or thing whatsoever occurring or existing on or
before the date of this Second Amendment, arising under, relating to or in
connection with the Amended Agreement (or any of the Exhibits or Schedules
thereto) and which are set forth in Schedule 2.1 to this Second Amendment.
                                    --------

               (b) Buyer hereby represents and warrants to Seller that, as of
the date of this Second Amendment, to Buyer's knowledge, Buyer does not have any
Claims against any Seller Party, other than as set forth in Schedule 2.1 to this
                                                            --------
Second Amendment, which Claims have been released and waived pursuant to Section
2.1(a).

          Section 2.2  Release and Waiver of Claims Against Buyer Parties.
                       ---------------------------------------------------

               (a) Seller and each of its Affiliates hereby unconditionally and
irrevocably releases, acquits and forever discharges Buyer and its Affiliates,
shareholders, officers, directors, employees, agents, representatives,
successors and assigns (collectively, the "Buyer Parties"), effective as of the
date hereof, of and from, and hereby unconditionally and irrevocably waives, any
and all Claims, that the Seller or any of its Affiliates alone or with any other
Person had, now has, or might hereafter have against the Buyer Parties or any of
them jointly and/or severally, for or by reason of any matter, circumstance,
event, action, omission, cause or thing whatsoever occurring or existing on or
before the date of this Second Amendment, arising under, relating to or in
connection with the Amended Agreement (or any of the Exhibits or Schedules
thereto) and which are set forth in Schedule 2.2 to this Second Amendment.
                                    --------

                                       4
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               (b) Seller hereby represents and warrants to Buyer that, as of
the date of this Second Amendment, to Seller's knowledge, Seller does not have
any Claims against any Buyer Party, other than as set forth in Schedule 2.2 to
                                                               --------
this Second Amendment, which Claims have been released and waived pursuant to
Section 2.2(a).

          Section 2.3  Disclosed Matters.  Pursuant to Section 6.6 of the
                       -----------------
Agreement, Buyer and Seller hereby acknowledge and agree that the supplemental
or amended disclosure set forth in the Schedules to the Amended Agreement being
delivered by Seller to Buyer contemporaneously with this Second Amendment and
dated as of the date hereof shall, for purposes of the Amended Agreement, as
further amended hereby, including for purposes of determining whether the
conditions to Closing set forth in Article VII of the Agreement are satisfied,
be deemed to have been disclosed as of January 18, 2000.

                                  ARTICLE III

                           Miscellaneous Provisions
                           ------------------------

          Section 3.1  Amendment and Modification.  Subject to applicable Law,
                       --------------------------
this Second Amendment may be amended, supplemented or otherwise modified only by
written agreement entered into by all Parties.

          Section 3.2  Waiver  of  Compliance; Consents.  To the extent
                       --------------------------------
permitted by applicable Law, any failure of any of the Parties to comply with
any covenant, agreement or condition set forth herein may be waived by the Party
entitled to the benefit thereof only by a written instrument signed by such
Party, but any such waiver shall not operate as a waiver of, or estoppel with
respect to, any prior or subsequent failure to comply therewith.

          Section 3.3  Notices.  All notices and other communications hereunder
                       -------
shall be in writing and shall be given in accordance with Section 10.8 of the
Agreement.

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          Section 3.4  Assignment.  This Second Amendment shall be binding upon
                       ----------
and inure to the benefit of the Parties and their respective successors and
permitted assigns, but neither this Second Amendment nor any of the rights,
interests, obligations or remedies hereunder shall be assigned by any Party
hereto, including by operation of law, without the prior written consent of the
other Parties, nor is this Second Amendment intended to confer upon any other
Person any rights, interests, obligations or remedies hereunder.  Without
limiting the generality of the foregoing, no provision of this Second Amendment
shall create any third-party beneficiary rights in any Employee or former
employee of Seller (including any beneficiary or dependent thereof) in respect
of continued employment or resumed employment, and no provision of this Second
Amendment shall create any rights in any such Persons in respect of any benefits
that may be provided, directly or indirectly, under any employee benefit plan or
arrangement except  as expressly provided for thereunder.  Notwithstanding the
foregoing, (i) Seller may assign all or any portion of its rights, interests,
obligations and remedies hereunder to Conectiv, a Delaware corporation, or any
of Conectiv's wholly owned subsidiaries; provided, however, that no such
                                         -----------------
assignment shall (A) materially impair or delay the consummation of the
transactions contemplated hereby or by the Amended Agreement or (B) relieve or
discharge Seller from any of its obligations hereunder or under the Amended
Agreement; and (ii) Buyer may assign all or any portion of its rights,
interests, obligations and remedies hereunder to (A) any of its wholly owned
subsidiaries or (B) a trustee, lending institution or other Person solely for
purposes of financing the transactions contemplated hereby; provided, however,
                                                            -----------------
that no such assignment shall (A) materially impair or delay the consummation of
the transactions contemplated hereby or by the Amended Agreement or (B) relieve
or discharge Buyer from any of its obligations hereunder or under the Amended
Agreement.

          Section 3.5  Governing Law.  This Second Amendment shall be governed
                       -------------
by and construed in accordance with the laws of the State of Delaware (without
giving effect to conflicts of law principles) as to all matters, including
validity, construction, effect, performance and remedies.  Venue in any and all
suits, actions and proceedings related to the subject matter of this Second
Amendment shall be in the state and federal courts located in and for the State
of Delaware (the "Courts"), which shall have exclusive jurisdiction for such
                  ------
purpose, and the Parties hereby irrevocably submit to the exclusive jurisdiction
of such courts and irrevocably waive the defense of an inconvenient forum to the
maintenance of any such suit, action or proceeding.  Service of process may be
made in any manner recognized by such Courts.  Each of the Parties hereby
irrevocably waives its right to a jury trial

                                       6<PAGE>

                                                                   Exhibit 10.49

REDACTED - OMITTED MATERIAL HAS BEEN FILED SEPARATELY WITH THE COMMISSION AND IS
DENOTED HEREIN BY ***

July 2, 2001

Robert S. Thomas
President & CEO
Charles & Colvard, Ltd,
P.O. Box 13533
Research Triangle Park, NC 27709-3533

This letter, when signed by both parties, will serve as an agreement between
Charles & Colvard, Ltd. (formerly C3, Inc.) and Cree, Inc. as set forth below
and will apply to SIC production crystals purchased by Charles & Colvard from
Cree, during the period of twelve months beginning January 1, 2001. This letter
agreement supersedes the parties' letter agreement dated December 7, 2000.

1. Charles & Colvard Intends to purchase and Cree intends to sell production
crystals in the quantities and according to the following schedule, and at a
price of *** per gram of "usable material," determined in the manner described
in Paragraph 3. Purchases of the indicated quantity for the 3 monthly periods
beginning 3/26/01 will be committed only upon issuance of a purchase order by
Charles & Colvard on or before 1/5/01 and Cree's written acceptance of such
order. Purchases of the indicated quantity for the monthly periods June 25
through December 23, 2001 will be committed only upon issuance of a purchase
order by Charles & Colvard and Cree's written acceptance of such order. The
price of *** per gram is contingent on purchase orders requesting minimum
monthly quantities of *** grams. Cree will quote lead times dependent on
business conditions at the time of issuance of the purchase order.

------------------------------------------------------------------
Delivery Period                       Forecasted quantity
                                      (grams)
------------------------------------------------------------------
  1/1/01 - 1/21/01                    *** grams
------------------------------------------------------------------
 1/22/01 - 2/18/01                    *** grams
------------------------------------------------------------------
 2/19/01 - 3/25/01                    *** grams
------------------------------------------------------------------
 3/26/01 - 4/22/01                    *** grams
------------------------------------------------------------------
 4/23/01 - 5/20/01                    *** grams
------------------------------------------------------------------
 5/21/01 - 6/24/01                    *** grams
------------------------------------------------------------------
 6/25/01 - 7/22/01                    *** grams
------------------------------------------------------------------
 7/23/01 - 8/19/01                    *** grams
------------------------------------------------------------------
 8/20/01 - 9/23/01                    *** grams
------------------------------------------------------------------
 9/24/01 - 10/21/01                   *** grams
------------------------------------------------------------------
10/22/01 - 11/18/01                   *** grams
------------------------------------------------------------------
11/19/01 - 12/23/01                   *** grams
------------------------------------------------------------------

2.   The quantity of "usable material" of crystals delivered to Charles &
Colvard pursuant to this agreement will be determined according to the
following:

     A.   Material will be graded using the same practices used by the parties
          to grade crystals during calendar 2000 and in accordance with
          Attachment A.

     B.   Grams of usable material will be calculated on a crystal by crystal
          basis according to the following equation:

          (usable mm) as a percent of total length of the crystal in mm
          multiplied by the actual weight of the crystal in grams.

          "Usable mm" has the meaning defined In Attachment A.

     C.   Crystals shipped to Charles & Colvard must contain at least *** grams
          of usable material for 2" crystals or *** grams for 3" crystals.
          Crystal diameter to be shipped will be 2" or 3" as determined by Cree.

     D.   All grading will be concluded in a timely manner and consistent with
          past practice.

4.   Charles & Colvard shall not be obligated to fund, and Cree shall not be
obligated to carry out, the development program described in the July 1,1998
Amended and Restated Development Agreement, as amended (the "Development
Agreement'), for the

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period from January 1, 2001 through December 31. 2002, and the term of the
Development Agreement is extended through December 31, 2002.

5. Except as provided above, purchases will be subject to the terms and
conditions of the Supply Agreement and the development program will be subject
to the terms and conditions of the Development Agreement.

6. The contents of this letter shall be considered "Confidential Information" of
each party subject to the provisions of Section S of the Supply Agreement.

If acceptable, please sign below and date to indicate Charles & Colvard's
binding agreement to these terms.

      /s/ Charles M. Swoboda                /s/ Robert S. Thomas
      -------------------------             ------------------------
      Charles M. Swoboda                    Robert S. Thomas
      President and CEO                     President & CEO

Attachment A
Specification of usable material:
Except where noted below, "Usable mm" is calculated by adding the length of net
"light" material plus 55% of the length of net "medium light" material.

Except where noted below, Net material is calculated as "light" or "medium
light" material, as applicable, minus the % yield loss caused by the color
grading green and the inclusions and defects listed below, determined in
accordance with the practices followed by the parties in grading production
crystals during calendar 2000.

The inclusions and defects considered in determining yield loss are:

ID       D-Type
1        ***
2        ***
3        ***
5        ***
6        ***
8        ***
9        ***

Note: The sum total of net medium light and non-gray net light included in the
"usable mm" . shall be limited to ***% of the total usable mm shipped in any
given fiscal month ( Le, the monthly periods defined in paragraph 1 of the
attached letter agreement). Beyond this limit, said material shipped for the
remainder of that month will not be included in "usable mm" calculations.

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