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
비행기의 바리오미터는 고도를 측정하는 데 사용됩니다.bihaenggiui bariometerneun godoreul cheugjeonghaneun de sayongdoemnida.The aircraft's variometer is used to measure altitude.