What do earth`s plates float on?

The Earth's plates do not actually float on anything. The theory that describes the movement and interaction of the Earth's plates is called plate tectonics. According to this theory, the Earth's lithosphere, which consists of several large and small plates, floats above the more fluid asthenosphere. The asthenosphere is a partially molten layer in the upper mantle, which allows for the movement of the plates.

To get an answer to this question, one can consult scientific sources such as geology textbooks, research papers, or reliable websites that provide information on plate tectonics. These sources will explain the theory of plate tectonics and the dynamics of the Earth's lithosphere and asthenosphere.