Question: who sings knock three times on the ceiling
[{'answer': 'Tony Orlando and Dawn'}, {'provenance': [{'wikipedia_id': '758416', 'title': 'Knock Three Times', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 593, 'bleu_score': 0.7028738583912421, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14988392364996769900}, 'section': 'Section::::Abstract.'}]}]