Question: when were red solo cups introduced to the market
[{'answer': '1970s', 'provenance': [{'wikipedia_id': '5775457', 'title': 'Solo Cup Company', 'start_paragraph_id': 4, 'start_character': 7, 'end_paragraph_id': 4, 'end_character': 12, 'bleu_score': 1.0, 'section': 'Section::::History.\n'}]}, {'provenance': [{'wikipedia_id': '5775457', 'title': 'Solo Cup Company', 'start_paragraph_id': 4, 'start_character': 0, 'end_paragraph_id': 4, 'end_character': 325, 'bleu_score': 0.962600167205617, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7593595592524855264}, 'section': 'Section::::History.\n'}]}]