Question: when did ringling brothers merge with barnum and bailey
[{'answer': '1919', 'provenance': [{'wikipedia_id': '531057', 'title': 'Ringling Bros. and Barnum & Bailey Circus', 'start_paragraph_id': 1, 'start_character': 331, 'end_paragraph_id': 1, 'end_character': 335, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '531057', 'title': 'Ringling Bros. and Barnum & Bailey Circus', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 658, 'bleu_score': 0.9609482256832901, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 18430044291074829898}, 'section': 'Section::::Abstract.'}]}]