Question: when did we break the speed of sound
[{'answer': '14 October 1947', 'provenance': [{'wikipedia_id': '166072', 'title': 'Sound barrier', 'start_paragraph_id': 33, 'start_character': 3, 'end_paragraph_id': 33, 'end_character': 18, 'bleu_score': 1.0, 'section': 'Section::::History.:Sound barrier officially broken in aircraft.\n'}]}, {'provenance': [{'wikipedia_id': '166072', 'title': 'Sound barrier', 'start_paragraph_id': 33, 'start_character': 0, 'end_paragraph_id': 33, 'end_character': 863, 'bleu_score': 0.9411393669001251, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6045708240099937023}, 'section': 'Section::::History.:Sound barrier officially broken in aircraft.\n'}]}]