Question: when did the first explorers come to america
[{'answer': '1492', 'provenance': [{'wikipedia_id': '24490545', 'title': 'Exploration of North America', 'start_paragraph_id': 6, 'start_character': 188, 'end_paragraph_id': 6, 'end_character': 192, 'bleu_score': 1.0, 'section': 'Section::::Age of Discovery and the search for the Northwest Passage.\n'}]}, {'provenance': [{'wikipedia_id': '24490545', 'title': 'Exploration of North America', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 652, 'bleu_score': 0.9817332376369081, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8657608725691751976}, 'section': 'Section::::Age of Discovery and the search for the Northwest Passage.\n'}]}]