Q: In this task, you're given a statement, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.
Context: After the outbreak of the First World War, a priority for the Royal Navy was to secure the approaches to the English Channel, to prevent elements of the German High Seas Fleet from breaking out into the Atlantic, Link Information: It is the smallest of the shallow seas around the continental shelf of Europe, covering an area of some 75000 km2. Question: What is the surface area of the body of water that the Royal Navy secured the approaches to after the outbreak of the First World War?
A:
Answer: 75000