Question: how long is tom hanks on the island in castaway
[{'answer': 'four years', 'provenance': [{'wikipedia_id': '44501', 'title': 'Cast Away', 'start_paragraph_id': 33, 'start_character': 109, 'end_paragraph_id': 33, 'end_character': 119, 'bleu_score': 1.0, 'section': 'Section::::Production.:Wilson the volleyball.\n'}]}, {'provenance': [{'wikipedia_id': '44501', 'title': 'Cast Away', 'start_paragraph_id': 33, 'start_character': 0, 'end_paragraph_id': 33, 'end_character': 788, 'bleu_score': 0.9844346099707091, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6006384251605184441}, 'section': 'Section::::Production.:Wilson the volleyball.\n'}]}]