Question: who sings backup on will you still love me tomorrow
[{'answer': 'Joni Mitchell', 'provenance': [{'wikipedia_id': '4962981', 'title': 'Will You Love Me Tomorrow', 'start_paragraph_id': 13, 'start_character': 145, 'end_paragraph_id': 13, 'end_character': 158, 'bleu_score': 1.0, 'section': 'Section::::Carole King version.:Background.\n'}]}, {'answer': 'James Taylor', 'provenance': [{'wikipedia_id': '4962981', 'title': 'Will You Love Me Tomorrow', 'start_paragraph_id': 13, 'start_character': 163, 'end_paragraph_id': 13, 'end_character': 175, 'bleu_score': 1.0, 'section': 'Section::::Carole King version.:Background.\n'}]}, {'provenance': [{'wikipedia_id': '4962981', 'title': 'Will You Love Me Tomorrow', 'start_paragraph_id': 13, 'start_character': 0, 'end_paragraph_id': 13, 'end_character': 460, 'bleu_score': 0.9408228243926111, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3198012811882163264}, 'section': 'Section::::Carole King version.:Background.\n'}]}]