Question: when did the ancient chinese civilization begin and end
[{'answer': '8500'}, {'answer': '256 BC', 'provenance': [{'wikipedia_id': '5760', 'title': 'History of China', 'start_paragraph_id': 2, 'start_character': 23, 'end_paragraph_id': 2, 'end_character': 29, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]