Question: what is the imaginary line running north and south
[{'answer': '( geographical ) meridian'}, {'answer': 'line of longitude', 'provenance': [{'wikipedia_id': '629028', 'title': 'Meridian (geography)', 'start_paragraph_id': 1, 'start_character': 28, 'end_paragraph_id': 1, 'end_character': 45, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '629028', 'title': 'Meridian (geography)', 'start_paragraph_id': 1, 'start_character': 28, 'end_paragraph_id': 1, 'end_character': 606, 'bleu_score': 0.7655641135405501, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4907945061734681352}, 'section': 'Section::::Abstract.'}]}]