Question: how many layers in the earth's core
[{'answer': 'two', 'provenance': [{'wikipedia_id': '1417149', 'title': 'Structure of the Earth', 'start_paragraph_id': 6, 'start_character': 41, 'end_paragraph_id': 6, 'end_character': 44, 'bleu_score': 1.0, 'section': 'Section::::Structure.\n'}]}, {'provenance': [{'wikipedia_id': '1417149', 'title': 'Structure of the Earth', 'start_paragraph_id': 20, 'start_character': 0, 'end_paragraph_id': 20, 'end_character': 291, 'bleu_score': 0.5740976509634861, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17802202748898609677}, 'section': 'Section::::Structure.:Core.\n'}]}]