Question: when was the vietnam veterans war memorial built
[{'answer': '1982', 'provenance': [{'wikipedia_id': '32713', 'title': 'Vietnam Veterans Memorial', 'start_paragraph_id': 3, 'start_character': 54, 'end_paragraph_id': 3, 'end_character': 58, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '32713', 'title': 'Vietnam Veterans Memorial', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 527, 'bleu_score': 0.948891840545617, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14923511516481893871}, 'section': 'Section::::Abstract.'}]}]