Question: who was the presiding officer at the constitutional convention
[{'answer': 'president of the Continental Congress', 'provenance': [{'wikipedia_id': '336528', 'title': 'President of the Continental Congress', 'start_paragraph_id': 16, 'start_character': 50, 'end_paragraph_id': 16, 'end_character': 87, 'bleu_score': 1.0, 'section': 'Section::::List of presidents.\n'}]}, {'provenance': [{'wikipedia_id': '336528', 'title': 'President of the Continental Congress', 'start_paragraph_id': 1, 'start_character': 58, 'end_paragraph_id': 1, 'end_character': 592, 'bleu_score': 0.8583926455222081, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6241368698079691908}, 'section': 'Section::::Abstract.'}]}]