听力原文： The environmental group Green Peace says that more than a hundred new contracts have been issued over the past five years for extensive logging in an area covering 15 million hectares of forest in the Democratic Republic of Congo. Copies of the contracts obtained by the campaigning group show that as an exchange for the agreement of local communities to grant 25-year concessions to the forest areas, some logging companies have offered them gifts worth less than 100 U. S. dollars, others have made promises that they've never been kept. Those logging contracts mentioned involve ______ hectares of forest in Congo.