write this line of longitude in words 15 degrees East name a continent on this meridian?

Answer 1

You already wrote it in words:  15 Degrees East Longitude.

The meridian 15° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Europe, Africa, the Atlantic Ocean, the Southern Ocean, and Antarctica to the South Pole. Three Continents.

Answer 2

I'm not sure what you trying to ask, but the meridian 15 degrees east of Greenwich says Europe or

Africa