Yes it is a reliable source
Explanation: it shows the earth all in one. Makes it easier to study
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Your question: What physical feature marks the eastern boundary of the cultural subregion known as European Russia..?
Your answer: The Ural Mountains physical feature marks the Eastern boundary o f the cultural subregion known as European Russia.
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2 tectonic plates meet at the regions edge
Answer: The Himalayan Mountains are at a convergence plate boundary between the Eurasian plate and the Indian plate.
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