Domestic air travel in the United States has virtually come to a halt, but thousands of planes are still flying. How long does it makes sense to keep doing that?
원문출처 : https://www.cnn.com/2020/03/24/business/domestic-air-travel-shutdown/index.html
원문출처 : https://www.cnn.com/2020/03/24/business/domestic-air-travel-shutdown/index.html