Question: HMS "Royal Oak" was one of how many, "Revenge"-class battleships, built for the Royal Navy during the First World War?

full_context: Document 1: HMS Royal Oak (08): HMS "Royal Oak" was one of five "Revenge"-class battleship s built for the Royal Navy during the First World War. Launched in 1914 and completed in 1916, "Royal Oak" first saw combat at the Battle of Jutland as part of the Grand Fleet. In peacetime, she served in the Atlantic, Home and Mediterranean fleets, more than once coming under accidental attack. The ship drew worldwide attention in 1928 when her senior officers were controversially court-martialled. Attempts to modernise "Royal Oak" throughout her 25-year career could not fix her fundamental lack of speed and by the start of the Second World War, she was no longer suited to front-line duty.
Document 2: HMS Barham (04): HMS "Barham" was a "Queen Elizabeth"-class battleship built for the Royal Navy during the early 1910s. Often used as a flagship, she participated in the Battle of Jutland during the First World War as part of the Grand Fleet. For the rest of the First World War, except for the inconclusive Action of 19 August 1916, her service during the war generally consisted of routine patrols and training in the North Sea.
Document 3: Number 13-class battleship: The "Number 13"-class battleship was a planned class of four fast battleships to be built for the Imperial Japanese Navy (IJN) during the 1920s. The ships never received any names, being known only as "Numbers 13–16". They were intended to reinforce Japan's "eight-eight fleet" of eight battleships and eight battlecruisers after the United States announced a major naval construction program in 1919. The "Number 13" class was designed to be superior to all other existing battleships, planned or building. After the signing of the Washington Naval Treaty in 1922, they were cancelled in November 1923 before construction could begin.
Document 4: Revenge-class battleship: The Revenge"-class battleships (listed as Royal Sovereign" class in several editions of "Jane's Fighting Ships", as with the 1919 and 1931 editions, and sometimes also known as the "R" class) were five battleships of the Royal Navy, ordered as the First World War loomed, and launched in 1914–16. There were originally to have been eight of the class, but two were later redesigned, becoming the "Renown"-class battlecruiser s, while the other, which was to have been named HMS "Resistance", was cancelled.
Document 5: Queen Elizabeth-class battleship: The "Queen Elizabeth"-class battleships were a class of five super-dreadnoughts of the Royal Navy commissioned in 1915–16. The lead ship was named after Elizabeth I of England. These battleships were superior in firepower, protection and speed to their Royal Navy predecessors of the "Iron Duke" class as well as preceding German classes such as the "König" class , although the corresponding "Bayern"-class ships were competitive except for being 2 kn slower. As such, the "Queen Elizabeth"s are generally considered the first fast battleships.
Document 6: Colossus-class battleship (1910): The "Colossus"-class battleships were a pair of dreadnought battleships built for the Royal Navy (RN) at the end of the first decade of the 20th century, the last 12 in battleships built for the RN. The sister ships spent their whole careers assigned to the Home and Grand Fleets, often serving as flagships. Aside from participating in the Battle of Jutland in May 1916, and the inconclusive Action of 19 August several months later, their service during the First World War generally consisted of routine patrols and training in the North Sea.
Document 7: Lion-class battleship: The "Lion"-class battleships were a class of six fast battleships designed for the Royal Navy in the late 1930s. They were a larger, improved version of the "King George V" class with 16 in guns. Only two ships were laid down before the Second World War began in September 1939 and a third was ordered during the war, but their construction was suspended shortly afterwards. Their design changed several times in response to the removal of treaty restrictions on size and in light of war experience. None of the other ships planned were laid down, although there was a proposal to modify one of the suspended ships into a hybrid battleship/aircraft carrier with two 16-inch gun turrets and a flight deck. The two ships already begun were scrapped after the end of the war.
Document 8: Queen Elizabeth-class battleship: The "Queen Elizabeth"-class battleships were a class of five super-dreadnoughts of the Royal Navy commissioned in 1915–16. The lead ship was named after Elizabeth I of England. These battleships were superior in firepower, protection and speed to their Royal Navy predecessors of the "Iron Duke" class as well as preceding German classes such as the "König" class , although the corresponding "Bayern"-class ships were competitive except for being 2 kn slower. As such, the "Queen Elizabeth"s are generally considered the first fast battleships.
Document 9: HMS Queen Mary: HMS "Queen Mary" was the last battlecruiser built by the Royal Navy before World War I. The sole member of her class, "Queen Mary" shared many features with the "Lion"-class battlecruiser s, including her eight 13.5 in guns. She was completed in 1913 and participated in the Battle of Heligoland Bight as part of the Grand Fleet in 1914. Like most of the modern British battlecruisers, she never left the North Sea during the war. As part of the 1st Battlecruiser Squadron, she attempted to intercept a German force that bombarded the North Sea coast of England in December 1914, but was unsuccessful. She was refitting in early 1915 and missed the Battle of Dogger Bank in January, but participated in the largest fleet action of the war, the Battle of Jutland in mid-1916. She was hit twice by the German battlecruiser "Derfflinger" during the early part of the battle and her magazines exploded shortly afterwards, sinking the ship.
Document 10: Rivadavia-class battleship: The "Rivadavia" class consisted of two battleships designed by the American Fore River Shipbuilding Company for the Argentine Navy. Named "Rivadavia" and "Moreno" after important figures in Argentine history, they were Argentina's entry in the South American dreadnought race and a counter to Brazil's two "Minas Geraes"-class battleship s.
Document 11: Prince Consort-class ironclad: The "Prince Consort" class of battleship were four Royal Navy wooden-hulled broadside ironclads: HMS "Royal Oak", HMS "Prince Consort", HMS "Ocean", and HMS "Caledonia". They were originally laid down as "Bulwark"-class battleships, but were converted to ironclads. "Royal Oak" was Britain's fifth ironclad battleship completed.
Document 12: Dreadnought: The dreadnought was the predominant type of battleship in the early 20th century. The first of its kind, the Royal Navy's "Dreadnought" , made such a strong impression on people's minds when launched in 1906 that similar battleships built subsequently were referred to generically as "dreadnoughts", and earlier battleships became known as "pre-dreadnoughts". "Dreadnought"' s design had two revolutionary features: an "all-big-gun" armament scheme, with more heavy-calibre guns than previous ships, and steam turbine propulsion. As dreadnoughts became a symbol of national power, the arrival of these new warships was a crucial catalyst in the intensifying naval arms race between the United Kingdom and Germany. With the launch of a single ship, "Dreadnought", the scales of naval power were reset overnight. As a result, dreadnought races sprang up around the world, including in South America, during the lead up to World War I. Successive designs increased rapidly in size and made use of improvements in armament, armour, and propulsion throughout the dreadnought era. Within five years, new battleships had outclassed "Dreadnought". These more powerful vessels were known as "super-dreadnoughts". Most of the original dreadnoughts were scrapped after the end of World War I under the terms of the Washington Naval Treaty, but many of the newer super-dreadnoughts continued to be used throughout World War II. The only surviving dreadnought is USS "Texas" , located near the San Jacinto Battleground State Historic Site.
Document 13: HMS Warspite (03): HMS "Warspite" was a "Queen Elizabeth"-class battleship built for the Royal Navy during the early 1910s. Her thirty-year career covered both world wars and took her across the Atlantic, Indian, Arctic and Pacific Oceans. She participated in the Battle of Jutland during the First World War as part of the Grand Fleet. Other than that battle, and the inconclusive Action of 19 August, her service during the war generally consisted of routine patrols and training in the North Sea.
Document 14: HMS Falmouth (1910): HMS "Falmouth" was a Town-class light cruiser built for the Royal Navy during the 1910s. She was one of four ships of the "Weymouth" sub-class. The ship was initially assigned to the Atlantic Fleet upon completion in 1911, but was reduced to reserve in mid-1913. When the First World War began in 1914, "Falmouth" was transferred to the 1st Light Cruiser Squadron (LCS) of the Grand Fleet and then the 3rd Light Cruiser Squadron at the end of the year. The ship participated in most of the early fleet actions, including the Battles of Heligoland Bight, Dogger Bank, and Jutland, but was only seriously engaged in the latter. She was torpedoed and sunk off Flamborough Head, Yorkshire by German submarines during the Action of 19 August 1916.
Document 15: HMS Royal Oak (1892): HMS "Royal Oak" was one of seven "Royal Sovereign"-class pre-dreadnought battleships built for the Royal Navy during the 1890s. Upon her completion in 1894, she was initially placed in reserve until mobilised in 1896 for service with the Flying Squadron. After returning briefly to reserve, the ship was assigned the following year to the Mediterranean Fleet. "Royal Oak" remained there until 1902 when she returned home; after a refit, the ship was assigned to the Home Fleet, where she served as the flagship of the fleet's second-in-command in 1904–05. "Royal Oak" was then reduced to reserve until she was taken out of service in 1911. The ship was sold for scrap in early 1914.
ground_truth: five