Question: how many floors in world trade center twin towers
[{'answer': '110', 'provenance': [{'wikipedia_id': '45645094', 'title': 'World Trade Center (1973–2001)', 'start_paragraph_id': 17, 'start_character': 357, 'end_paragraph_id': 17, 'end_character': 360, 'bleu_score': 1.0, 'section': 'Section::::Design and construction.:Design.\n'}]}]