Question: when did the canadian pacific railway start and end
[{'answer': 'between 1968 and 1996', 'provenance': [{'wikipedia_id': '5959', 'title': 'Canadian Pacific Railway', 'start_paragraph_id': 1, 'start_character': 67, 'end_paragraph_id': 1, 'end_character': 88, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '5959', 'title': 'Canadian Pacific Railway', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 322, 'bleu_score': 0.8196190579071291, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11215500743770524833}, 'section': 'Section::::Abstract.'}]}]