Question: what type of steel is used in rebar
[{'answer': 'unfinished tempered steel', 'provenance': [{'wikipedia_id': '234417', 'title': 'Rebar', 'start_paragraph_id': 18, 'start_character': 24, 'end_paragraph_id': 18, 'end_character': 49, 'bleu_score': 1.0, 'section': 'Section::::Physical characteristics.\n'}]}, {'provenance': [{'wikipedia_id': '234417', 'title': 'Rebar', 'start_paragraph_id': 18, 'start_character': 0, 'end_paragraph_id': 18, 'end_character': 1557, 'bleu_score': 0.9852911663954631, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7746265977717813802}, 'section': 'Section::::Physical characteristics.\n'}]}]