Black Friday: lifetime access is on a special offer in the app, until November 30. Black Friday: special offer on lifetime access, until November 30. Download
지구의 장동회전성은 천체의 움직임에 영향을 미칩니다.jiguui jangdonghoetjeonseong-eun cheontaeui umjigime yeonghyang-eul michimnida.The nutation of the Earth affects the movement of celestial bodies.