Question: how many senators are there in united states
[{'answer': '100', 'provenance': [{'wikipedia_id': '31756', 'title': 'United States Congress', 'start_paragraph_id': 1, 'start_character': 451, 'end_paragraph_id': 1, 'end_character': 454, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]