Question: who has the tie breaking vote in senate
[{'answer': 'Vice President', 'provenance': [{'wikipedia_id': '3493102', 'title': 'List of tie-breaking votes cast by vice presidents of the United States', 'start_paragraph_id': 0, 'start_character': 35, 'end_paragraph_id': 0, 'end_character': 49, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]