Question: what is on the floor of the colosseum
[{'answer': 'sand', 'provenance': [{'wikipedia_id': '49603', 'title': 'Colosseum', 'start_paragraph_id': 41, 'start_character': 127, 'end_paragraph_id': 41, 'end_character': 131, 'bleu_score': 1.0, 'section': 'Section::::Physical description.:Arena and hypogeum.\n'}]}, {'provenance': [{'wikipedia_id': '49603', 'title': 'Colosseum', 'start_paragraph_id': 41, 'start_character': 0, 'end_paragraph_id': 41, 'end_character': 939, 'bleu_score': 0.9866213202385071, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3970286874356491706}, 'section': 'Section::::Physical description.:Arena and hypogeum.\n'}]}]