Answer: architecture, and good construction engineers.
Explanation: hope this will help you
<span>Ultramafic rocks contain "olivine," and are commonly found in "mantle."
mantle is a inner layer of a planet and makes up about 84% of the planet. Ultramafic rocks are found in layers, so naturally you will find this in the mantle layer of the planet.
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Answer:
Movement in the mantle caused by variations in heat from the core, cause the plates to shift, which can cause earthquakes and volcanic eruptions.