Detailed Instructions: This task involves creating questions from a given passage that involve some kind of complex reasoning (including numerical reasoning).
The generated questions must require looking at more than one part of the passage to answer. Try to use a variety of reasoning types in your questions (some of the sample reasoning types are illustrated in the 'positive examples' field) and also have a variety of answer types (spans, numbers, dates). A span is a continuous phrase taken directly from the passage or question. In such questions, the answer spans are recommended to be five words. Questions with answer type "number", are expected to start with "How many". For instance, "How long did an event last?" can be phrased as "How many years did an event last?". To increase diversity, try to create more questions for which the answer will be multiple spans. Please create questions that require AT LEAST 2 arithmetic operations as illustrated in the 'positive examples' field. You are encouraged to try DIFFERENT COMBINATIONS of operations and not just limit to the combinations shown in those examples. The more challenging questions you create, the better it is.
Q: Passage: With the death of Admiral Stepan Makarov during the siege of Port Arthur in April 1904, Admiral Wilgelm Vitgeft was appointed commander of the battle fleet and was ordered to make a sortie from Port Arthur and deploy his force to Vladivostok. Flying his flag in the French-built pre-dreadnought Tsesarevich, Vitgeft proceeded to lead his six battleships, four cruisers, and 14 torpedo boat destroyers into the Yellow Sea in the early morning of 10 August 1904. Waiting for him was Admiral Togo and his fleet of four battleships, 10 cruisers, and 18 torpedo boat destroyers. At approximately 12:15, the battleship fleets obtained visual contact with each other, and at 13:00 with Togo crossing Vitgeft's T, they commenced main battery fire at a range of about eight miles, the longest ever conducted up to that time. For about thirty minutes the battleships pounded one another until they had closed to less than four miles and began to bring their secondary batteries into play. At 18:30, a hit from one of Togo's battleships struck Vitgeft's flagship's bridge, killing him instantly. With the Tsesarevich's helm jammed and their admiral killed in action, she turned from her battle line, causing confusion among her fleet. However, Togo was determined to sink the Russian flagship and continued pounding her, and it was saved only by the gallant charge of the American-built Russian battleship Retvizan, whose captain successfully drew away Togo's heavy fire from the Russian flagship. Knowing of the impending battle with the battleship reinforcements arriving from Russia , Togo chose not to risk his battleships by pursuing his enemy as they turned about and headed back into Port Arthur, thus ending naval history's longest-range gunnery duel up to that time and the first modern clash of steel battleship fleets on the high seas.
A:
How many miles did the ships travel toward each other after the commenced firing?