Question: when did the amazon river become the longest
[{'answer': '16 June 2007', 'provenance': [{'wikipedia_id': '922586', 'title': 'List of rivers by length', 'start_paragraph_id': 10, 'start_character': 387, 'end_paragraph_id': 10, 'end_character': 399, 'bleu_score': 1.0, 'section': 'Section::::List of rivers longer than 1000 km.:Notes.\n'}]}, {'provenance': [{'wikipedia_id': '922586', 'title': 'List of rivers by length', 'start_paragraph_id': 10, 'start_character': 0, 'end_paragraph_id': 10, 'end_character': 926, 'bleu_score': 0.9874601949752461, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 18046213694575470373}, 'section': 'Section::::List of rivers longer than 1000 km.:Notes.\n'}]}]