Question: when did the national civil rights museum open
[{'answer': 'September 28 , 1991', 'provenance': [{'wikipedia_id': '1217028', 'title': 'National Civil Rights Museum', 'start_paragraph_id': 13, 'start_character': 81, 'end_paragraph_id': 13, 'end_character': 100, 'bleu_score': 1.0, 'section': 'Section::::History.:Museum opening in 1991.\n'}]}, {'provenance': [{'wikipedia_id': '1217028', 'title': 'National Civil Rights Museum', 'start_paragraph_id': 13, 'start_character': 0, 'end_paragraph_id': 13, 'end_character': 155, 'bleu_score': 0.9271474438253491, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6236630539196249389}, 'section': 'Section::::History.:Museum opening in 1991.\n'}]}]