EXHIBIT 99.1
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                            Explanation of Responses
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(1)  GMAM Investment Funds Trust II (the "Trust"), a group trust organized for
     the benefit of certain trusts under certain employee benefit plans, holds
     the securities referred to in line 2 of table 1 (the "Securities"). The
     reporting person ("GMIMCO") has retained under the Employee Retirement
     Income Security Act of 1974, as amended, the power to direct the voting and
     disposition of the Securities although it has no pecuniary interest
     therein. General Motors Trust Company is the trustee (the "Trustee") with
     respect to the Trust. GMIMCO is serving as investment manager with respect
     to the Trust and in that capacity it has the sole power to direct the
     Trustee as to the voting and disposition of the Securities. Line 1 of Table
     1 relates to GMIMCO's and the Trustee's status as a 10% beneficial owner
     without pecuniary interest with respect to the Securities. Line 2 of Table
     1 relates to the status of the Trust on behalf of which GMIMCO is making
     the report reflected on such line as a 10% beneficial owner that may have a
     pecuniary interest in the Securities. This filing should not be deemed an
     admission that any of GMIMCO, the Trustee or the Trust is the beneficial
     owner of the Securities.