Question: how many ships did the union have in the civil war
[{'answer': '671', 'provenance': [{'wikipedia_id': '5953763', 'title': 'Union Navy', 'start_paragraph_id': 8, 'start_character': 482, 'end_paragraph_id': 8, 'end_character': 485, 'bleu_score': 1.0, 'section': 'Section::::Ships.\n'}]}, {'provenance': [{'wikipedia_id': '5953763', 'title': 'Union Navy', 'start_paragraph_id': 8, 'start_character': 0, 'end_paragraph_id': 8, 'end_character': 493, 'bleu_score': 0.9427836745142131, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 1180685111636888112}, 'section': 'Section::::Ships.\n'}]}]