Question: what does the area under the curve show
[{'answer': 'total drug exposure over time'}, {'provenance': [{'wikipedia_id': '23518221', 'title': 'Area under the curve (pharmacokinetics)', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 272, 'bleu_score': 0.8527204701689131, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5315157101018796611}, 'section': 'Section::::Interpretation and usefulness of AUC values.\n'}]}]