SIGNATURE

     After reasonable inquiry and to the best of the knowledge and belief of each of the undersigned, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

Dated: August 2, 2010

PEARSON PLC
By:	/s/ John Makinson
	Name:	John Makinson
	Title:	Director
PEARSON OVERSEAS HOLDINGS LTD.
By:	/s/ David Colville
	Name:	David Colville
	Title:	Director
PEARSON NETHERLANDS B.V.
By:	/s/ Alan Miller
	Name:	Alan Miller
	Title:	Director
PEARSON LUXEMBOURG HOLDINGS NO. 2 LTD.
By:	/s/ Alan Miller
	Name:	Alan Miller
	Title:	Director
PEARSON LUXEMBOURG HOLDINGS SARL
By:	/s/ Alan Miller
	Name:	Alan Miller
	Title:	Director
PEARSON NETHERLANDS HOLDINGS B.V.
By:	/s/ David Colville
	Name:	David Colville
	Title:	Director

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PEARSON INC.
By:	/s/ Thomas Wharton
	Name:	Thomas Wharton
	Title:	Senior Vice President
PEARSON LONGMAN, INC.
By:	/s/ Thomas Wharton
	Name:	Thomas Wharton
	Title:	Vice President
PEARSON DBC HOLDINGS INC.
By:	/s/ Thomas Wharton
	Name:	Thomas Wharton
	Title:	Vice President

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