Final answer:
Britain came to the aid of Russia during World War I by attacking the Ottoman Empire through the failed invasion of Gallipoli.
Step-by-step explanation:
During World War I, Britain provided aid to Russia by attacking the Ottoman Empire. British troops were sent to the Gallipoli Peninsula in an attempt to open up supply routes to Russia through the Dardanelles. However, this invasion of Gallipoli ultimately failed and did not provide the expected assistance to Russia.
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