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
상대등제는 사회적 불평등을 줄이는 데 중요한 개념입니다.sangdaejeungjeneun sahoejeok bulpyeongdeungeul julineun de jungyohan gaenyeomimnida.Relative equality is an important concept in reducing social inequality.