Question: who plays mark and luke on the following
[{'answer': 'Sam Underwood', 'provenance': [{'wikipedia_id': '40162191', 'title': 'Sam Underwood', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 13, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '40162191', 'title': 'Sam Underwood', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 202, 'bleu_score': 0.646574624222234, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14101301264298311310}, 'section': 'Section::::Abstract.'}]}]