Question: what is the si unit for magnetic field strength
[{'answer': 'amperes per meter'}, {'answer': 'teslas or newtons per meter per ampere'}, {'provenance': [{'wikipedia_id': '36563', 'title': 'Magnetic field', 'start_paragraph_id': 2, 'start_character': 19, 'end_paragraph_id': 2, 'end_character': 613, 'bleu_score': 0.5477397448705961, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9044127852051502283}, 'section': 'Section::::Abstract.'}]}]