Identify the geographical line of reference shown in the image. Image text: к востоку от Гринвича 180 к западу от Гринвича

The geographical line of reference shown is the Prime Meridian (also known as the Greenwich Meridian) and the International Date Line (180th meridian). Explanation: The text 'к востоку от Гринвича 180 к западу от Гринвича' indicates the reference lines related to the Prime Meridian and the 180th meridian. 'к востоку от Гринвича' means 'east of Greenwich', and 'к западу от Гринвича' means 'west of Greenwich'. The 180th meridian is often considered the International Date Line.