Question: when was the first subway sandwich shop opened
[{'answer': 'In 1968', 'provenance': [{'wikipedia_id': '54581', 'title': 'Subway (restaurant)', 'start_paragraph_id': 9, 'start_character': 515, 'end_paragraph_id': 9, 'end_character': 522, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '54581', 'title': 'Subway (restaurant)', 'start_paragraph_id': 9, 'start_character': 0, 'end_paragraph_id': 9, 'end_character': 561, 'bleu_score': 0.978606533029418, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12806142472892457674}, 'section': 'Section::::History.\n'}]}]