Question: when was the land rover first unveiled to the public
[{'answer': '1947', 'provenance': [{'wikipedia_id': '18724', 'title': 'Land Rover', 'start_paragraph_id': 5, 'start_character': 51, 'end_paragraph_id': 5, 'end_character': 55, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '18724', 'title': 'Land Rover', 'start_paragraph_id': 14, 'start_character': 0, 'end_paragraph_id': 14, 'end_character': 126, 'bleu_score': 0.8914703664390791, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 13214141656052834823}, 'section': 'Section::::History.:Timeline.\n'}]}]