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
열기관은 열 에너지를 기계적 에너지로 변환합니다.yeolgigan-eun yeol eoneojireul gijaejeog eoneojilo byeonhwanhamnida.A heat engine converts thermal energy into mechanical energy.