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                                    FORM OF
                       WARRANT FOR PURCHASE OF SHARES OF
                                COMMON STOCK OF
                               LSC, INCORPORATED

                                  May 15, 1998

         For value received, ______________________, or his registered assigns
(the "Holder"), is entitled to purchase from LSC, Incorporated, a Minnesota
corporation (the "Company"), at any time on or before May 15, 2003,
__________________________________ (______) fully paid and nonassessable shares
of the Company's Common Stock, $.01 par value (such class of stock being
hereinafter referred to as the "Common Stock" and such Common Stock as may be
acquired upon exercise hereof being hereinafter referred to as the "Warrant
Stock"), at an exercise price equal to 80% of the per unit price of securities
sold by LSC in its next round of equity financing that raises gross proceeds of
at least $1,000,000.

         This Warrant is described in, and is subject to the terms and
provisions of, the Contribution and Security Agreement, dated as of May 15,
1998, among the Company and the other parties thereto (the "Agreement"). The
provisions of the Agreement are incorporated herein by reference with the same
force and effect as if fully set forth herein.

         This Warrant is subject to the following provisions, terms and
conditions:

         1. The rights represented by this Warrant may be exercised by the
Holder, in whole or in part (but not as to a fractional share of Common Stock),
by written notice of exercise delivered to the Company accompanied by the
surrender of this Warrant (properly endorsed if required) at the principal
office of the Company and upon payment to it, by cash, certified check or bank
draft, of the warrant exercise price for such shares. In addition, the Holder
may elect to pay the full purchase price by receiving a number of shares of
Common Stock computed using the following formula:

                  X = Y(A-B)
                      ------
                        A

Where:            X =  the number of shares of Common Stock to be issued to the
                       Holder.

                  Y =  the number of shares of Common Stock as to which this
                       Warrant is being exercised.

                  A =  the Fair Market Value of one share of Common Stock.

                  B =  Warrant Exercise Price.

         "Fair Market Value" means, with respect to the Company's Common Stock,
as of any date:

                  (a) if the Common Stock is listed or admitted to unlisted
         trading privileges on any national securities exchange or is not so
         listed or admitted but transactions in the Common Stock are reported on
         the Nasdaq National Market, the reported closing price of

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         the Common Stock on such exchange or by the Nasdaq National Market as
         of such date (or, if no shares were traded on such day, as of the next
         preceding day on which there was such a trade); or

                  (b) if the Common Stock is not so listed or admitted to
         unlisted trading privileges or reported on the Nasdaq National Market,
         and bid and asked prices therefor in the over-the-counter market are
         reported by Nasdaq or National Quotation Bureau, Inc. (or any
         comparable reporting service), the mean of the closing bid and asked
         prices as of such date, as so reported by Nasdaq or, if not so reported
         thereon, as reported by National Quotation Bureau, Inc. (or such
         comparable reporting service); or

                  (c) if the Common Stock is not so listed or admitted to
         unlisted trading privileges, or reported on the Nasdaq National Market,
         and such bid and asked prices are not so reported by Nasdaq or National
         Quotation Bureau, Inc. (or any comparable reporting service), such
         price as the Company's Board of Directors determines in good faith in
         the exercise of its reasonable discretion.

         The Company agrees that the Warrant Stock so purchased shall be and are
deemed to be issued as of the close of business on the date on which this
Warrant shall have been surrendered and payment made for such Warrant Stock as
aforesaid. Certificates for the shares of Warrant Stock so purchased shall be
delivered to the Holder within 15 days after the rights represented by this
Warrant shall have been so exercised, and, unless this Warrant has expired, a
new Warrant representing the number of Warrant Stock, if any, with respect to
which this Warrant has not been exercised shall also be delivered to the Holder
within such time. Notwithstanding the foregoing, however, the Company shall not
be required to deliver any certificates for the Warrant Stock, except in
accordance with the provisions and subject to the limitations of Section 5
below.

         2. The Company covenants and agrees that all shares of Warrant Stock
that may be issued upon the exercise of this Warrant will, upon issuance, be
duly authorized and issued, fully paid and nonassessable and free from all
taxes, liens and charges with respect to the issuance thereof. The Company
further covenants and agrees that until expiration of this Warrant, the Company
will at all times have authorized, and reserved for the purpose of issuance or
transfer upon exercise of this Warrant, a sufficient number of shares of Common
Stock to provide for the exercise of this Warrant.

         3. The foregoing provisions are, however, subject to the following:

                     (a) The Warrant exercise price shall be subject to
         adjustment from time to time as hereinafter provided. Upon each
         adjustment of the Warrant exercise price, the holder of this Warrant
         shall thereafter be entitled to purchase, at the Warrant exercise price
         resulting from such adjustment, the number of shares obtained by
         multiplying the Warrant exercise price in effect immediately prior to
         such adjustment by the number of shares purchasable pursuant hereto
         immediately prior to such adjustment and dividing the product thereof
         by the Warrant exercise price resulting from such adjustment.

                     (b) In case the Company shall at any time subdivide the
         outstanding Common Stock into a greater number of shares or declare a
         dividend payable in Common Stock,


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         the Warrant exercise price in effect immediately prior to such
         subdivision shall be proportionately reduced, and conversely, in case
         the outstanding Common Stock shall be combined into a smaller number of
         shares, the Warrant exercise price in effect immediately prior to such
         combination shall be proportionately increased.

                     (c) If any capital reorganization or reclassification of
         the capital stock of the Company, or consolidation or merger of the
         Company with another corporation, or the sale of all or substantially
         all of its assets to another corporation shall be effected in such a
         way that holders of Common Stock shall be entitled to receive stock,
         securities or assets ("substituted property") with respect to or in
         exchange for such Common Stock, then, as a condition of such
         reorganization, reclassification, consolidation, merger or sale, the
         Holder shall have the right to purchase and receive upon the basis and
         upon the terms and conditions specified in this Warrant and in lieu of
         the Common Stock of the Company immediately theretofore purchasable and
         receivable upon the exercise of the rights represented hereby, such
         substituted property as would have been issued or delivered to the
         Holder if it had exercised this Warrant and had received upon exercise
         of this Warrant the Common Stock prior to such reorganization,
         reclassification, consolidation, merger or sale. The Company shall not
         effect any such consolidation, merger or sale, unless prior to the
         consummation thereof the successor corporation (if other than the
         Company) resulting from such consolidation or merger or the corporation
         purchasing such assets shall assume by written instrument executed and
         mailed to the Holder at the last address of the Holder appearing on the
         books of the Company, the obligation to deliver to the Holder such
         shares of stock, securities or assets as, in accordance with the
         foregoing provisions, the Holder may be entitled to purchase.

                     (d) Upon any adjustment of the Warrant exercise price, the
         Company shall give written notice thereof, by first-class mail, postage
         prepaid, addressed to the Holder at the address of the Holder as shown
         on the books of the Company, which notice shall state the Warrant
         exercise price resulting from such adjustment and the increase or
         decrease, if any, in the number of shares purchasable at such price
         upon the exercise of this Warrant, setting forth in reasonable detail
         the method of calculation and the facts upon which such calculation is
         based.

         4. This Warrant shall not entitle the Holder to any voting rights or
other rights as a shareholder of the Company.

         5. The Holder, by acceptance hereof, represents and warrants that (a)
it is acquiring this Warrant for its own account for investment purposes only
and not with a view to its resale or distribution and (b) it has no present
intention to resell or otherwise dispose of all or any part of this Warrant.
Other than pursuant to registration under federal and state securities laws or
an exemption from such registration, the availability of which the Company shall
determine in its sole discretion, (y) the Company will not accept the exercise
of this Warrant or issue certificates for shares of Warrant Stock and (z)
neither this Warrant nor any shares of Warrant Stock may be sold, pledged,
assigned or otherwise disposed of (whether voluntarily or involuntarily). The
Company may condition such issuance or sale, pledge, assignment or other
disposition on the receipt from the party to whom this Warrant is to be so
transferred or to whom Warrant Stock is to be issued or so transferred of any
representations and agreements requested by the Company


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in order to permit such issuance or transfer to be made pursuant to exemptions
from registration under federal and applicable state securities laws. Each
certificate representing the Warrant (or any part thereof) and any shares of
Warrant Stock shall be stamped with appropriate legends setting forth these
restrictions on transferability. The Holder, by acceptance hereof, agrees to
give written notice to the Company before exercising or transferring this
Warrant or transferring any shares of Warrant Stock of the Holder's intention to
do so, describing briefly the manner of any proposed exercise or transfer.
Within thirty (30) days after receiving such written notice, the Company shall
notify the Holder as to whether such exercise or transfer may be effected.

         6. This Warrant shall be transferable only on the books of the Company
by the Holder in person, or by duly authorized attorney, on surrender of the
Warrant, properly assigned.

         7. Neither this Warrant nor any term hereof may be changed, waived,
discharged or terminated orally but only by an instrument in writing signed by
the party against which enforcement of the change, waiver, discharge or
termination is sought.

         IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by
its duly authorized officer and to be dated as of the date set forth above.

                                    LSC, INCORPORATED

                                    By:
                                       -----------------------------------------
                                       J. B. Balogh

                                    Its: President and Chief Executive Officer

THE SECURITIES EVIDENCED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES
ACT OF 1933 OR APPLICABLE STATE SECURITIES LAWS. THESE SECURITIES HAVE BEEN
ACQUIRED FOR INVESTMENT AND MAY NOT BE OFFERED FOR SALE, SOLD, PLEDGED, ASSIGNED
OR OTHERWISE DISPOSED OF, AND NO TRANSFER OF THE SECURITIES WILL BE MADE BY THE
COMPANY OR ITS TRANSFER AGENT, IN THE ABSENCE OF SUCH REGISTRATION OR AN OPINION
OF COUNSEL ACCEPTABLE TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED.


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