Question: what was the spruce goose made out of
[{'answer': 'almost entirely of birch', 'provenance': [{'wikipedia_id': '197878', 'title': 'Hughes H-4 Hercules', 'start_paragraph_id': 1, 'start_character': 596, 'end_paragraph_id': 1, 'end_character': 620, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '197878', 'title': 'Hughes H-4 Hercules', 'start_paragraph_id': 1, 'start_character': 15, 'end_paragraph_id': 1, 'end_character': 1033, 'bleu_score': 0.868574107950105, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8437349053851764916}, 'section': 'Section::::Abstract.'}]}]