Question: when did plan b become available over the counter
[{'answer': 'August 24 , 2006'}, {'provenance': [{'wikipedia_id': '18939', 'title': 'Emergency contraception', 'start_paragraph_id': 74, 'start_character': 0, 'end_paragraph_id': 74, 'end_character': 266, 'bleu_score': 0.955027111100031, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 2364190193663645944}, 'section': 'Section::::History.:United States.:Plan B.\n'}]}]