Question: what percentage of the population was killed in ww2
[{'answer': '3 %', 'provenance': [{'wikipedia_id': '240900', 'title': 'World War II casualties', 'start_paragraph_id': 1, 'start_character': 130, 'end_paragraph_id': 1, 'end_character': 135, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]