Question: when did 50 stars get on the american flag
[{'answer': 'July 1960', 'provenance': [{'wikipedia_id': '11447', 'title': 'Flag of the United States', 'start_paragraph_id': 3, 'start_character': 326, 'end_paragraph_id': 3, 'end_character': 335, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '11447', 'title': 'Flag of the United States', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 419, 'bleu_score': 0.82948653056981, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5177904223238247325}, 'section': 'Section::::History.\n'}]}]