What is the world's largest sea by surface area?

Which sea is located between the Italian Peninsula and the Balkan Peninsula? What is the world's deepest ocean? What is the world's saltiest body of water? Which ocean has the highest tides? Which strait connects the Atlantic Ocean to the Mediterranean Sea? What is the name of the sea that separates the islands of Great Britain and Ireland? Which sea is located between the Scandinavian Peninsula and the British Isles? What is the name of the sea that is located between the Korean Peninsula and the Japanese archipelago?