Question: who does plankton's voice in spongebob squarepants
[{'answer': 'Mr. Lawrence', 'provenance': [{'wikipedia_id': '42348013', 'title': 'List of SpongeBob SquarePants cast members', 'start_paragraph_id': 6, 'start_character': 109, 'end_paragraph_id': 6, 'end_character': 121, 'bleu_score': 1.0, 'section': 'Section::::Regular cast.:Background.\n'}]}]