Question: representatives elected to the senate serve how many year terms
[{'answer': 'staggered terms of six years', 'provenance': [{'wikipedia_id': '24909346', 'title': 'United States Senate', 'start_paragraph_id': 2, 'start_character': 295, 'end_paragraph_id': 2, 'end_character': 323, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '24909346', 'title': 'United States Senate', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 598, 'bleu_score': 0.5290195987042681, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3330656256957142950}, 'section': 'Section::::Abstract.'}]}]