Question: who played mckenna in mckenna shoots for the stars
[{'answer': 'Jade Pettyjohn', 'provenance': [{'wikipedia_id': '43740584', 'title': 'An American Girl: McKenna Shoots for the Stars', 'start_paragraph_id': 1, 'start_character': 172, 'end_paragraph_id': 1, 'end_character': 186, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]