Question: where is corn mostly grown in the u.s
[{'answer': 'west / north central Iowa', 'provenance': [{'wikipedia_id': '39564241', 'title': 'Corn production in the United States', 'start_paragraph_id': 1, 'start_character': 241, 'end_paragraph_id': 1, 'end_character': 268, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'east central Illinois', 'provenance': [{'wikipedia_id': '39564241', 'title': 'Corn production in the United States', 'start_paragraph_id': 1, 'start_character': 269, 'end_paragraph_id': 1, 'end_character': 290, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '39564241', 'title': 'Corn production in the United States', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 332, 'bleu_score': 0.767102318821929, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10451729244606037548}, 'section': 'Section::::Abstract.'}]}]