Question: when did the mgm grand open in vegas
[{'answer': 'December 18 , 1993', 'provenance': [{'wikipedia_id': '699781', 'title': 'MGM Grand Las Vegas', 'start_paragraph_id': 10, 'start_character': 36, 'end_paragraph_id': 10, 'end_character': 54, 'bleu_score': 1.0, 'section': 'Section::::History.:MGM Grand (1993–present).\n'}]}, {'provenance': [{'wikipedia_id': '699781', 'title': 'MGM Grand Las Vegas', 'start_paragraph_id': 10, 'start_character': 0, 'end_paragraph_id': 10, 'end_character': 1083, 'bleu_score': 0.9895009487746611, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5465042410374995539}, 'section': 'Section::::History.:MGM Grand (1993–present).\n'}]}]