What is the name of the largest island in the Baltic Sea?

What is the name of the third-largest island in the world? In which continent is the island of Greenland located? In which country is the island of Sumatra located? In which country is the island of Java located? In which country is the island of Corsica located? Which island is the second-largest island in the Mediterranean Sea? What is the largest island in the Indian Ocean? Which island is the largest in the Bismarck Archipelago?