Question: where have winter olympics been in the us
[{'answer': 'Salt Lake City'}, {'answer': 'Lake Placid', 'provenance': [{'wikipedia_id': '11015817', 'title': 'List of Olympic Games host cities', 'start_paragraph_id': 4, 'start_character': 346, 'end_paragraph_id': 4, 'end_character': 357, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Squaw Valley'}]