Question: who has the biggest gdp in the world
[{'answer': 'The United States', 'provenance': [{'wikipedia_id': '380845', 'title': 'List of countries by GDP (nominal)', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 17, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '380845', 'title': 'List of countries by GDP (nominal)', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 530, 'bleu_score': 0.942340155314736, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7271636809233605371}, 'section': 'Section::::Abstract.'}]}]