Question: how much does it cost to make a stealth bomber
[{'answer': '$737 million', 'provenance': [{'wikipedia_id': '4396', 'title': 'Northrop Grumman B-2 Spirit', 'start_paragraph_id': 2, 'start_character': 517, 'end_paragraph_id': 2, 'end_character': 528, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]