Which of the layers of the Earth has the following characteristics? i. It is solid and extremely hot. ii. It is the innermost layer of the Earth. iii. It is around 800 miles thick.

The inner core is the Earth’s innermost layer and is solid because of the immense pressure, even though it is extremely hot. It is roughly 800 miles thick, so the best answer is the inner core. The outer core is liquid, while the crust and mantle are not the innermost layer.

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