The layer of Earth that has a liquid and solid layer is the mantle.

Here's a breakdown:

* Solid layer: The upper part of the mantle is solid, but it's still very hot and behaves like a very viscous fluid over long periods.

* Liquid layer: The lower part of the mantle is mostly liquid, with a very high pressure that prevents it from boiling. This liquid layer is crucial for the movement of tectonic plates.

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