Question: how many ships were sunk by german u boats in ww1
[{'answer': '5,000', 'provenance': [{'wikipedia_id': '22620358', 'title': 'U-boat Campaign (World War I)', 'start_paragraph_id': 3, 'start_character': 52, 'end_paragraph_id': 3, 'end_character': 57, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '22620358', 'title': 'U-boat Campaign (World War I)', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 157, 'bleu_score': 0.735928772715101, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3438535511260676945}, 'section': 'Section::::Abstract.'}]}]