Question: on which river is the annual boatrace between oxford and cambridge universities rowed
[{'answer': 'the River Thames', 'provenance': [{'wikipedia_id': '247877', 'title': 'The Boat Race', 'start_paragraph_id': 1, 'start_character': 173, 'end_paragraph_id': 1, 'end_character': 189, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '247877', 'title': 'The Boat Race', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 293, 'bleu_score': 0.9333603884339721, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14160523889696570655}, 'section': 'Section::::Abstract.'}]}]