What is the porosity of the gravel sample? A)
95%
B)
55%
C)
40%
D)
38%

4. Ancient sandstone beaches become buried deep beneath the Earth’s surface, where they are exposed to extreme heat and pressure.

Explanation:

Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot mineral-rich fluids or, more commonly, some combination of these factors. Conditions like these are found deep within the Earth or where tectonic plates meet.