Question: where is the world tallest building the burj khalifa located
[{'answer': 'Dubai , United Arab Emirates', 'provenance': [{'wikipedia_id': '794957', 'title': 'Burj Khalifa', 'start_paragraph_id': 1, 'start_character': 140, 'end_paragraph_id': 1, 'end_character': 168, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '794957', 'title': 'Burj Khalifa', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 333, 'bleu_score': 0.5420529722951041, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9226756445991225484}, 'section': 'Section::::Abstract.'}]}]