Question: when did jack in the box introduce tacos
[{'answer': '1950s', 'provenance': [{'wikipedia_id': '166778', 'title': 'Jack in the Box', 'start_paragraph_id': 15, 'start_character': 144, 'end_paragraph_id': 15, 'end_character': 149, 'bleu_score': 1.0, 'section': 'Section::::Products.\n'}]}, {'provenance': [{'wikipedia_id': '166778', 'title': 'Jack in the Box', 'start_paragraph_id': 15, 'start_character': 0, 'end_paragraph_id': 15, 'end_character': 1076, 'bleu_score': 0.9656439184149831, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4930845668455156315}, 'section': 'Section::::Products.\n'}]}]