Question: how many american casualties in the battle of midway
[{'answer': '307', 'provenance': [{'wikipedia_id': '60112', 'title': 'Battle of Midway', 'start_paragraph_id': 89, 'start_character': 91, 'end_paragraph_id': 89, 'end_character': 94, 'bleu_score': 1.0, 'section': 'Section::::Japanese and US casualties.\n'}]}, {'provenance': [{'wikipedia_id': '60112', 'title': 'Battle of Midway', 'start_paragraph_id': 89, 'start_character': 0, 'end_paragraph_id': 89, 'end_character': 347, 'bleu_score': 0.9374009563674951, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12640234582356324804}, 'section': 'Section::::Japanese and US casualties.\n'}]}]