Question: when did amazon start selling things other than books
[{'answer': '1998', 'provenance': [{'wikipedia_id': '58634020', 'title': 'History of Amazon', 'start_paragraph_id': 10, 'start_character': 303, 'end_paragraph_id': 10, 'end_character': 307, 'bleu_score': 1.0, 'section': 'Section::::Online bookstore and IPO.\n'}]}]