Question: what are the different fields of mechanical engineering
[{'answer': 'applied mechanics'}, {'answer': 'dynamics', 'provenance': [{'wikipedia_id': '19528', 'title': 'Mechanical engineering', 'start_paragraph_id': 2, 'start_character': 94, 'end_paragraph_id': 2, 'end_character': 102, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'thermodynamics', 'provenance': [{'wikipedia_id': '19528', 'title': 'Mechanical engineering', 'start_paragraph_id': 2, 'start_character': 104, 'end_paragraph_id': 2, 'end_character': 118, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'fluid mechanics', 'provenance': [{'wikipedia_id': '19528', 'title': 'Mechanical engineering', 'start_paragraph_id': 108, 'start_character': 73, 'end_paragraph_id': 108, 'end_character': 88, 'bleu_score': 1.0, 'section': 'Section::::Areas of research.:Computational fluid dynamics.\n'}]}, {'answer': 'heat transfer', 'provenance': [{'wikipedia_id': '19528', 'title': 'Mechanical engineering', 'start_paragraph_id': 78, 'start_character': 76, 'end_paragraph_id': 78, 'end_character': 89, 'bleu_score': 1.0, 'section': 'Section::::Subdisciplines.:Thermodynamics and thermo-science.\n'}]}, {'answer': 'production technology'}]