Question: when did the first episode of that 70s show air
[{'answer': 'August 23 , 1998', 'provenance': [{'wikipedia_id': '274551', 'title': "That '70s Show", 'start_paragraph_id': 23, 'start_character': 36, 'end_paragraph_id': 23, 'end_character': 60, 'bleu_score': 1.0, 'section': 'Section::::Episodes.:Timeline.\n'}]}, {'provenance': [{'wikipedia_id': '274551', 'title': "That '70s Show", 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 270, 'bleu_score': 0.9269343237061861, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7689331444151528204}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '274551', 'title': "That '70s Show", 'section': 'Section::::Episodes.:Timeline.\n', 'start_paragraph_id': 23, 'end_paragraph_id': 23, 'meta': {'evidence_span': ['The show was set in May 1976 in the August 23, 1998 premiere. After 12 episodes, the series transitioned to 1977. The 23rd episode, "Grandma\'s Dead", was also set in 1976, because it was s', 'The show was set in May 1976 in the August 23, 1998 premiere']}}]}]