Question: the paleolithic age man used a hard stone
[{'answer': '2.6 million years ago', 'provenance': [{'wikipedia_id': '22860', 'title': 'Paleolithic', 'start_paragraph_id': 10, 'start_character': 104, 'end_paragraph_id': 10, 'end_character': 125, 'bleu_score': 1.0, 'section': 'Section::::Paleogeography and climate.\n'}]}, {'provenance': [{'wikipedia_id': '22860', 'title': 'Paleolithic', 'start_paragraph_id': 31, 'start_character': 0, 'end_paragraph_id': 31, 'end_character': 519, 'bleu_score': 0.9735040436119741, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 779353227265395299}, 'section': 'Section::::Human way of life.:Technology.:Tools.\n'}]}]