Question: who built the first gear-driven mechanical calculator that did addition and subtraction
[{'answer': 'Wilhelm Schickard', 'provenance': [{'wikipedia_id': '432897', 'title': 'Mechanical calculator', 'start_paragraph_id': 2, 'start_character': 21, 'end_paragraph_id': 2, 'end_character': 38, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '432897', 'title': 'Mechanical calculator', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 740, 'bleu_score': 0.9651324673660481, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10126687323479151328}, 'section': 'Section::::Abstract.'}]}]