Question: where is the matrix located in the mitochondria
[{'answer': 'within the inner membrane', 'provenance': [{'wikipedia_id': '1329361', 'title': 'Mitochondrial matrix', 'start_paragraph_id': 1, 'start_character': 46, 'end_paragraph_id': 1, 'end_character': 71, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1329361', 'title': 'Mitochondrial matrix', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 541, 'bleu_score': 0.9751504244977051, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8487761166348725117}, 'section': 'Section::::Abstract.'}]}]