Question: who is the ice cream truck killer in dexter
[{'answer': 'Rudy Cooper', 'provenance': [{'wikipedia_id': '23981878', 'title': 'Dexter (season 1)', 'start_paragraph_id': 1, 'start_character': 708, 'end_paragraph_id': 1, 'end_character': 719, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]