The section of Earth composed primarily of liquid metal is the outer core.

Here's a breakdown:

* Earth's Structure: The Earth is made up of several layers: the crust, the mantle, the outer core, and the inner core.

* Outer Core: This layer is located about 1,800 to 2,890 kilometers below the Earth's surface. It's primarily composed of liquid iron and nickel, with smaller amounts of other elements like sulfur, silicon, and oxygen.

* Liquid Metal: The extreme pressure and heat in the outer core keep these metals in a liquid state.

* Earth's Magnetic Field: The movement of liquid metal within the outer core generates Earth's magnetic field, which protects us from harmful solar radiation.

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