Question: when did canada give alaska to the usa
[{'answer': '1903', 'provenance': [{'wikipedia_id': '558426', 'title': 'Alaska boundary dispute', 'start_paragraph_id': 1, 'start_character': 188, 'end_paragraph_id': 1, 'end_character': 192, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '558426', 'title': 'Alaska boundary dispute', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 684, 'bleu_score': 0.87458029594828, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 2008539457992320912}, 'section': 'Section::::Abstract.'}]}]