Question: how many episodes are in vikings season 2
[{'answer': 'ten', 'provenance': [{'wikipedia_id': '40419770', 'title': 'Vikings (season 2)', 'start_paragraph_id': 1, 'start_character': 167, 'end_paragraph_id': 1, 'end_character': 170, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '40419770', 'title': 'Vikings (season 2)', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 421, 'bleu_score': 0.972407137066537, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 1647757509457649647}, 'section': 'Section::::Abstract.'}]}]