Question: who was president of the us in 1990
[{'answer': 'George Herbert Walker Bush', 'provenance': [{'wikipedia_id': '11955', 'title': 'George H. W. Bush', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 26, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]