Q: Given a paragraph from a Wikipedia article about some topic, and a question related to the topic, determine whether the question is answerable from the paragraph. If the question is answerable, answer "True", otherwise, answer "False".
During the period of North–South division, Nanjing remained the capital of the Southern dynasties for more than two and a half centuries. During this time, Nanjing was the international hub of East Asia. Based on historical documents, the city had 280,000 registered households. Assuming an average Nanjing household had about 5.1 people at that time, the city had more than 1.4 million residents. Question: Alerts for air pollution issued by the cities affected by the smog were likely removed by when?
A:
False