Question: what are the pieces in a domino set
[{'answer': 'rectangular tile', 'provenance': [{'wikipedia_id': '8262', 'title': 'Dominoes', 'start_paragraph_id': 1, 'start_character': 98, 'end_paragraph_id': 1, 'end_character': 114, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '8262', 'title': 'Dominoes', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 705, 'bleu_score': 0.90024839018386, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12386860928966306974}, 'section': 'Section::::Abstract.'}]}]