Prime Meridian : The imaginary line running from north to south through the Royal Observatory in Greenwich, England which is assigned a longitude of 0 degrees and is therefore used as the reference point for all other lines of longitude.
👇 ស្វែងរកឯកសាររៀននិងការងារគ្រប់ប្រភេទនៅទីនេះ៖
👇 ស្វែងរកពាក្យផ្សេងទៀតនៅប្រអប់នេះ៖