Question: when was agent orange first used in korea
[{'answer': 'the late 1960s', 'provenance': [{'wikipedia_id': '2547', 'title': 'Agent Orange', 'start_paragraph_id': 102, 'start_character': 28, 'end_paragraph_id': 102, 'end_character': 42, 'bleu_score': 1.0, 'section': 'Section::::Use outside Vietnam.:Brazil.\n'}]}, {'provenance': [{'wikipedia_id': '2547', 'title': 'Agent Orange', 'start_paragraph_id': 112, 'start_character': 0, 'end_paragraph_id': 112, 'end_character': 48, 'bleu_score': 0.8070557274927981, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15863526388851543153}, 'section': 'Section::::Use outside Vietnam.:Korea.\n'}]}]