Question: what city is in the center of the us
[{'answer': 'Lebanon', 'provenance': [{'wikipedia_id': '5385152', 'title': 'Geographic center of the contiguous United States', 'start_paragraph_id': 3, 'start_character': 90, 'end_paragraph_id': 3, 'end_character': 97, 'bleu_score': 1.0, 'section': 'Section::::Overview.\n'}]}]