Question: who measured the magnitude of the positive charge on the nucleus
[{'answer': 'George Stoney', 'provenance': [{'wikipedia_id': '9804', 'title': 'Electric charge', 'start_paragraph_id': 15, 'start_character': 57, 'end_paragraph_id': 15, 'end_character': 70, 'bleu_score': 1.0, 'section': 'Section::::Units.\n'}]}, {'provenance': [{'wikipedia_id': '9804', 'title': 'Electric charge', 'start_paragraph_id': 15, 'start_character': 0, 'end_paragraph_id': 15, 'end_character': 584, 'bleu_score': 0.866662562215553, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8862299059753664533}, 'section': 'Section::::Units.\n'}]}]