Question: who has the best batting average in mlb history
[{'answer': 'Ty Cobb', 'provenance': [{'wikipedia_id': '47426323', 'title': 'List of Major League Baseball career batting average leaders', 'start_paragraph_id': 2, 'start_character': 11, 'end_paragraph_id': 2, 'end_character': 18, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '47426323', 'title': 'List of Major League Baseball career batting average leaders', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 627, 'bleu_score': 0.9823771291847391, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9349044851768353010}, 'section': 'Section::::Abstract.'}]}]