سلسلة بيو بيو كسارة الصخور الفوسفات
كسارات فكية سلسلة بيو. كسارة فكية سلسلة بيو كسارة سامنة The parsec symbol pc is a unit of length used to measure the large distances to astronomical objects outside the Solar System A parsec is obtained by the use of parallax and trigonometry and is defined as the distance at which one astronomical unit subtends an angle of one arcsecond ie 1/3600th ...