Question: who played mr. carter in welcome back carter
[{'answer': 'Gabe Kaplan', 'provenance': [{'wikipedia_id': '384163', 'title': 'Welcome Back, Kotter', 'start_paragraph_id': 1, 'start_character': 52, 'end_paragraph_id': 1, 'end_character': 63, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '384163', 'title': 'Welcome Back, Kotter', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 295, 'bleu_score': 0.758654541281487, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10301547151585889046}, 'section': 'Section::::Abstract.'}]}]