A complete circle is 360 degrees, and it was once thought that there were 360 days in the year, so 1 degree marked one day in the orbit of the Earth round the sun
First correct your figure a circule has 360 and not 380 degree when 4 angles of 90 degree joint each other a complete circle comes in its shape the total of 4 angels of 90 degree is 360 so we can say that a circle has 360 degree more about this question please contect onnaonn54@yahoo,com