Question: when did america start building the panama canal
[{'answer': 'late nineteenth century', 'provenance': [{'wikipedia_id': '2869783', 'title': 'History of the Panama Canal', 'start_paragraph_id': 2, 'start_character': 7, 'end_paragraph_id': 2, 'end_character': 30, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2869783', 'title': 'History of the Panama Canal', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 543, 'bleu_score': 0.9757530668325981, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 18178816691400984392}, 'section': 'Section::::Abstract.'}]}]