Answer:
When hot magma cools, igneous rocks are formed.
b) When graphite is under higher pressure and heat, it becomes diamond.
c) Igneous rocks include pumice and granite and can be formed above Eath's surface.
d) Metamorphic rocks are formed when existing rocks are changed inside Earth.
Step-by-step explanation:
Magma is the molten rocks that is found inside Earth’s surface. Its the lava that is stored inside the Earth’s surface. This magma formes out of the Earth's surface during a volcanic eruption, or cools inside the Earth's surface itself to form igneous rock.
Graphite and diamond both are the allotropes of carbon. This is the change in allotropes which can occur in extreme cases of temperatures or pressure which can occur inside the Earth’s surface. This can change graphite to diamond.
Igneous rocks which are externally formed are pumice or basalt which forms when lava comes out of Earth's interior and cools to form rock. Whereas the Igneous rocks like granite are formed when the magma cools inside the Earth’s surface due to cooling of lava.
Metamorphic rocks are formed when the Igneous or sedimentary rocks undergoes conditions of severe temperature or pressure from inside the Earth's surface and the structure of the rock fully changes. This is how the metamorphic rocks form.