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
지형선은 지도에서 고도를 나타내는 중요한 요소입니다.jihyeongseoneun jidoui godeureul natananeun jungyohan yosoimnida.The contour line is an important element that indicates elevation on a map.